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Marder III: German Tank Destroyer on a Czech Chassis

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The start of the Great Patriotic War on June 22nd, 1941, triggered serious corrections to both Soviet and German tank building. The fighting in 1941 showed that the time of light tanks is coming to an end. At the same time, the increasing mass of more and more powerful anti-tank weapons limited their ability to be transported by their crews. The abilities of the German PzI Ausf. B tank were limited, and it was impossible to create anything more powerful than the Panzerjager I. It's not surprising that the Germans came up with the idea to create SPGs using the chassis of other obsolete light tanks. This article will discuss the family of Marder III tank destroyers, which were built on the chassis of the Pz38(t).


Path of least resistance

The situation with the Pz38(t) in 1941 could be called critical. This tank was technically classified as light, but in practice these types of tanks performed the same tasks as the medium PzIII. It's not surprising that these tanks suffered record losses. 772 tanks were present in the German army as of June 22nd, 1941, and 796 were destroyed by the end of the year. No other German tank came close to this "record". It was clear that the career of the Pz38(t) was coming to an end.

At the same time, there were no issues with the chassis. Out of all light tanks produced in Germany and on occupied territories, it was the product of the BMM factory (CKD before the occupation) that showed the most promise. The size of the chassis and the capabilities of the suspension allowed the vehicles to be converted into SPGs with relative ease.

Pz.Sfl.2 from the 1st production batch, spring 1942. The gun travel clamp, which broke down often, can be seen.

A decision to design a tank destroyer using the Pz38(t) chassis was made on December 22nd, 1941. In 6 (Inspekteur für Heeresmotorisierung, Inspector of Motorized Forces) gave the order to the 6th Department of the Armament Directorate only two days after an analogous program using the La.S.138 (PzII Ausf. D and E) was launched. Like the 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.II(F) (Sfl.), the requirements were hard to meet. Since the SPG was needed as soon as possible, changes to the chassis had to be minimal. The requirements were sent to BMM, which was also instructed to produce a prototype.

The same vehicle from the rear. The design of the fighting compartment allows the vehicle to carry additional ammunition crates in the rear.

The task of converting the gun was given to Rheinmetall-Borsig, who was also working on the 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.II(F) (Sfl.) at the time. It is not surprising that the gun mount for the new SPG was very similar. The oscillating part was taken from the Pak 36(r), which was made by converting captured Soviet F-22 guns. In addition to new ammunition, the Pak 36(r) had an altered aiming mechanism, a telescopic sight, and a muzzle brake. A gun shield was added to protect the crew not only from the front, but partially from the sides. The design of the shield was almost identical to that of the 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.II(F) (Sfl.), but with the difference that the plates were joined by rivets. This was because BMM was not yet capable of welding armour.

A second production batch vehicle is easy to distinguish due to a new gun clamp.

BMM's designers had a tough job with the chassis. As the requirements demanded, the Pz.Sfl.2 had to retain the old chassis design. Even the turret platform was preserved (sans roof). The designers were faced with the same issues with this conversion as with the La.S.138. The layout with a central crankshaft made matters more complicated. The designers were forced to make a massive cross-shaped mount and attach it to the front plate and sides of the turret platform. More armour was added to the sides and front in addition to the armour of the turret platform. Like with the tank destroyer on the La.S.138 chassis, the fighting compartment was partially on top of the engine deck.

This photo shows how the tarp is attached.

It's hard to call this solution ideal, since the overall height grew to 2.5 meters. Nevertheless, BMM performed better in their task than the team that designed the 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.II(F) (Sfl.). For starters, accessing the engine was easier. Removing the gearbox was still a difficult task, however. The position of the driver and radio operator was also better. They had their own hatches and did not have to crawl through the fighting compartment to access their stations. The space underneath the gun was also used more rationally, keeping 30 shells close to the loader and gunner. The mass of the vehicle was 10.8 tons, almost a ton less than the analogous vehicle on the chassis of the La.S.138. Finally, the bore axis was 20 cm lower, which improved stability during firing.

Pz.Sfl.2 für 7,62 cm Pak 36 from the third production batch.

Contract #219/326/42H for 120 Pz.Sfl.2 was signed with BMM on March 6th, 1942. The expected rate of production was as follows: 24 by March 24th, another 16 by March 31st, 70 by April 28th, and 17 by May 5th. The contract for 500 Pz38(t) tanks remained in effect. Despite that, BMM managed to fulfil most of the March quota: 33 Pz.Sfl.2 were made. The issue was not with production of the chassis, but with shipments of guns. The supplies seriously impacted the production in April. instead of 70 units, only 35 were shipped.

Officially, all of these SPGs, including the March production, were accepted in April. This is when the name 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.38(t) (Sfl), "76.2 mm Pak 36(r) gun on a Pz38(t) self propelled chassis", was used. The remaining 52 SPGs were delivered in May of 1942. Some of them were built as tropical variants. According to proud German tradition, the SPGs were renamed constantly. 5 different names were used in 1942 alone. The name Pz.Sfl.2 für 7,62 cm Pak 36, first used in July of 1942, was the most commonly used one. The index Sd.Kfz.132 was also applied around this time.

Pz.Sfl.2 für 7,62 cm Pak 36, converted from a refurbished Pz38(t).

Production didn't stop here. At a meeting on May 7th, 1942, Hitler declared that the Pz38(t) was obsolete. Tank destroyers should be built instead of these tanks. At a meeting on May 13th, it was decided that at least 20 Pz.Sfl.2 für 7,62 cm Pak 36 should be built every month. The final decision regarding the future of the Pz38(t) was made on June 4th. The order for the second batch of tank destroyers was made on that day, and regular tanks were removed from production. Their chassis would be used to make SPGs.

26 Pz38(t) tanks and 23 Pz.Sfl.2 für 7,62 cm Pak 36 tank destroyers were delivered in June. The tanks of the second batch were slightly different from the first. A small change allowed the gun depression to be increased by 2 degrees. The travel clamp was also converted. All SPGs built in June had tropical equipment. Another 50 Pz.Sfl.2 für 7,62 cm Pak 36 were built in July, the remaining 27: in August.

A captured tank destroyer at the NIBT proving grounds, summer 1943.

Production of the third batch began in August of 1943. Externally, these SPGs had slightly different hatches in the driver's compartment. In addition, some vehicles received more powerful Praga AC engines. The top speed increased to 47 kph thanks to this 150 hp engine. In total, 344 Pz.Sfl.2 für 7,62 cm Pak 36 were built between the three batches, with chassis numbers between 1360-1479 and 1527-1750. Production of SPGs of this type did not end here. Starting in February of 1943, Pz38(t) tanks that returned from the front were converted. About 30 vehicles were made this way.

The Pz.Sfl.2 für 7,62 cm Pak 36 began to enter service in May of 1942. Unlike PzII SPGs, these vehicles were sent to tank divisions, not tank destroyer battalions. An exception was the 521st Tank Destroyer Battalion, where 12 vehicles were sent on May 27th, 1942. A tank division usually received a battery of 6 SPGs. There were, however, cases where a division received 9 (18th TD) or 12 (8th and 19th TDs) SPGs. One of the first recipients were the 15th and 21st Tank Divisions, which were fighting in North Africa. Later, 39 tank destroyers of this type were sent to North Africa. The trend of sending the Pz.Sfl.2 für 7,62 cm Pak 36 to tank divisions continued after that.

The same vehicle from the left.

The SPGs first went into battle in July of 1942. Reviews were similar to those that came in for the 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.II(F) (Sfl.). First of all, they had to do with the gun, or rather its height. The tall vehicle made an excellent target, and the bulletproof armour offered little protection. Many complaints were made regarding the location of the ammunition. At certain traverse angles, the gun and shield covered the ammunition racks. Many complaints were made about the travel lock as well.

There was also positive feedback. The armour piercing shell confidently punched through the front of a KV-1 tank from 350 meters, and this was not the limit. A negative feature of the gun was the muzzle brake, which kicked up a cloud of dust during firing.

A major difference from the reviews of the 7,62 cm Pak 36(r) auf Fgst. Pz.Kpfw.II(F) (Sfl.) was that there were few complaints regarding the reliability of the vehicle. Complains came in regarding the weak leaf spring mounting, the occasional transmission breakdown, and poor traction. According to reviews, the vehicle was mobile, had a good suspension, and did not make much noise. Significant issues were only faced in North Africa. Despite the conversions made for hot climates, the vehicles were ill-suited for this theater. The engines suffered the most, and broke down often.

A photo from the rear shows the fighting compartment.

The finale of the 1942 campaign had a direct impact on the number of Pz.Sfl.2 für 7,62 cm Pak 36. 94 vehicles of this type remained in the Wehrmacht by June 30th, 1943, 8 of which were undergoing repairs. In July of 1943 they were renamed Panzerjäger 38 7,62 cm Pak 36 and received the index Sd.Kfz.139. Only 38 vehicles survived until the end of the year, when they were named Marder III. This name was used very infrequently. 

These SPGs lasted until the end of the war. As of January 22nd, 1945, 23 of these SPGs were listed as still in service. Only two remain to this day. One is in Fort Lee, USA, and the other can be seen in France, in the Saumur tank museum.

Moving to the Pak 40

Using the Pak 36(r) as a main weapon of tank destroyers was a half-measure. The biggest issue with this gun was that the number of available guns was limited. Production of the F-22 ended before the war, and no new batches of trophies could be expected. The Germans understood this perfectly, and the question of rearming the Pz38(t) tank destroyer was raised in early March of 1942.

 7.5 cm Stu.Kan. auf Pz.Kpfw.38(t). This project did not move past the production of a prototype.

Interestingly enough, the first choice was not an anti-tank gun. On March 8th, 1942, Hitler proposed the installation of the 75 mm StuK 40 L/43 on the Pz38(t) chassis. Preparation for production of the StuG 40 Ausf F armed with this gun were underway. The idea was reasonable, as the StuK 40 had more compact recoil elements. And so, the 7.5 cm Stu.Kan. auf Pz.Kpfw.38(t) was born. The chassis was developed by BMM, and the gun by Alkett. Unlike the Pz.Sfl.2 für 7,62 cm Pak 36, the SPG had a much larger gun shield, which was much more effective at protecting the crew. The vehicle also retained the stock driver's compartment hatches. However, the 7.5 cm Stu.Kan. auf Pz.Kpfw.38(t) never saw mass production. It turned out to be easier to use the slightly more powerful Pak 40 gun.

Sfl.38 prototype, June 1942.

On May 7th, 1942, at the same meeting where Hitler questioned the further production of the Pz38(t), he also raised the issue of producing a tank destroyer armed with a 7.5 cm Pak 40 gun. Calculations showed that there would be no issue with installing this gun. A prototype of the vehicle named 7.5 cm Pak 40 auf Pz.Kpfw.38(t) passed trials in Milovice by the end of June.

Production 7.5 cm Pak 40 auf Pz.Kpfw.38(t). The photo shows how the tarp was attached.

The layout of the chassis, also referred to as Sfl.38, was radically different from the previous SPG. On one hand, it was also built with the requirement to avoid changes to the Pz38(t) chassis. The turret platform was also preserved, sans roof. On the other hand, the fighting compartment was completely different. Instead of a mobile shield, a casemate was installed, open from the rear and partially from the sides and the top. This design was much more effective at protecting the crew from small arms fire. The mount used in the Pak 40 remained, but was reduced in size. The amount of ammunition carried increased to 38 rounds. In addition, extra crates could fit on the platform installed above the engine compartment. The platform was built in such a way that it did not impede the servicing of the engine.

Instead of large seats, the commander/gunner and loader received small ones. The new vehicle did away with the driver and radio operator's hatches. This change in the layout allowed the mass to remain at the previous level. The height of the vehicle was the same (2.5 meters), but the bore axis height was lowered to 1.96 meters.

The layout of this vehicle was superior to the  Pz.Sfl.2 für 7,62 cm Pak 36.

The German brass was satisfied with the new SPG. The first 24 vehicles were planned for August of 1942, but the plans had to be moved down. Production of the third batch of the  Pz.Sfl.2 für 7,62 cm Pak 36 began at that time, which meant that new production could not start until November. The delay was beneficial for the new SPG, since it meant that all new vehicles were built with the more powerful Praga AC engine. Production of 50 7.5 cm Pak 40 auf Pz.Kpfw.38(t) was planned for the first month, but only 42 were accepted in reality. The difference was made up in December, when BMM put out 68 SPGs.

An SPG that was made via conversion of a refurbished Pz38(t).

The age of the 7.5 cm Pak 40 auf Pz.Kpfw.38(t) was a short one. The last 6 SPGs of this type left BMM in May of 1943. In total, 275 vehicles of this type with chassis numbers in the 1751-2075 and 2121-2147 ranges. Conversion of refurbished Pz38(t) vehicles also began in May. 175 tanks were converted this way.

A captured 7.5 cm Pak 40/3 auf Sfl.38 (Ausf.H). NIBT proving grounds, summer 1943.

These SPGs entered service in January of 1943. The shipments were irregular, and often happened as a part of reinforcements. Initially tank units had priority, but the situation changed in the spring of 1943. Losses led to the SPGs, renamed 7.5 cm Pak 40/3 auf Sfl.38 (Ausf.H) in May of 1943, were sent to independent tank destroyer battalions (559, 616, 731, 742, 743, 744). The number of incoming vehicles was irregular. The 731st battalion received 36 SPGs, more than anyone else. The others got 13 to 16 SPGs. These vehicles were also used in tank destroyer battalions that were a part of infantry divisions.

The same vehicle from the left. The crew is reliably protected from bullets and shrapnel.

Reviews from the front lines were similar to those for the Pz.Sfl.2 für 7,62 cm Pak 36. The fact that the Wehrmacht was not doing too well in February of 1943 influenced the impression that the 7.5 cm Pak 40/3 auf Sfl.38 (Ausf.H) left. By this point, the Germans were defending instead of attacking. The Red Army retained the initiative until March of 1943. In addition, the StuG 40 Ausf. G began entering service en masse. 197 Stug 40 Ausf. G were built in March of 1943, and 260 in May. Certainly, the 7.5 cm Pak 40/3 auf Sfl.38 (Ausf.H) was better than a towed Pak 40, but the vehicle had a tall silhouette and not the thickest armour. Compared to that, the StuG 40's 80 mm of front armour and low profile made it look much more appealing.

The same vehicle from the front. The unit emblem is visible.

173 7.5 cm Pak 40/3 auf Sfl.38 (Ausf.H) were in service on June 30th, 1943, 10 of which were undergoing repairs. These vehicles participated in Operation Citadel, which had a great impact on their numbers. It's hard to say how many vehicles survived until the end of 1943, as they were lumped in with later models. This vehicle was renamed 7 times during its service. The last name used was 7.5 cm Pak 40/3 Sfl. Marder 38T with the index Sd.Kfz.138. Two SPGs of this type survive to this day: one in the museum in Sinsheim, Germany, the other in Trieste, Italy.

Lightly armoured optimum

A positive experience in converting the PzII Ausf. F into the leFH 18/2 (Sf) auf GW II inspired a similar conversion of the Pz38(t). BMM received an order for the development of the Motor vorn SPG in February of 1943. The layout of the chassis was similar to that of the GW II. The engine and cooling system were moved to the front, and the driver's compartment was drastically reduced in size. The radio operator was removed, and the driver received a separate cabin. Moving the engine compartment forward allowed the creation of a roomy fighting compartment in the rear, which fit three crewmen: the commander, the gunner, and the loader.

Initial production 7.5 cm Pak 43/3 auf Sfl.38 (Ausf.M) Motor vorn. This vehicle has distinctive rear fenders, which were later deleted.

The gun mount was also similar. The oscillating part of the Pak 40/3 was installed on a mount above the engine compartment. This solution freed up some room, but caused a heap of problems. To reach the engine, one had to first remove the front plates of the casemate, then the gun, and then the mount. However, these problems were tolerable, since the benefits of this layout were worth it. The thickness of the armour was also sacrificed to reduce mass. As a result, the mass grew, but not by much, only to 11 tons.

Main production batch vehicle, 1943.

The resulting chassis was accepted. The German army finally received a tank destroyer where the commander only had one job. In addition, the improved layout of the fighting compartment finally allowed easy access to the ammunition. It's not surprising that the production of the vehicle, named  7.5 cm Pak 43/3 auf Sfl.38 (Ausf.M) Motor vorn, began in May of 1943. 20 vehicles were delivered in the first month of production, 45 in June, and 90 in July. This made it possible to stop production of vehicles on the PzII chassis and focus on the more in-demand  leFH 18/2 (Sf) auf GW II.

The name of the vehicle was changed to Panzerjäger 38 by the end of the summer, with the index Sd.Kfz.138. As for the name Marder III that is widely used in modern literature, it was first used in November of 1943. However, the classification did not differentiate between the Marder III Ausf. H and Marder III Ausf. M. No such index was ever used.

The same vehicle from the front. The serial number on the front plate suggests that it was built in May of 1943.

Various changes were made to the design during production. The Praga Ausf.IV 180 hp engine was used starting in July of 1943. During its service, it turned out that it suffered from poor reliability. The solution was to replace it with the 160 hp Praga Typ NS in November of 1943. It was less powerful, but more reliable. A commander's version with additional radio equipment was introduced in the summer of 1943. Its installation reduced the ammunition capacity by 26 rounds.

The biggest change to the design of the Panzerjäger 38 happened in November of 1943. By that time, BMM had finally mastered welding, and the driver's cabin and hull became welded. The fighting compartment casemate was still assembled with rivets.

A redesigned layout allowed the creation of a fighting compartment for three crewmen.

The Panzerjäger 38 became the second most common German tank destroyer. 634 vehicles of this type were built in 1943. Potentially BMM could have built more, but the chassis was used in other SPGs starting in late 1943. It's not surprising that the production numbers began to drop. The peak of production was reached in October, when BMM produced 141 vehicles. Production numbers dropped to 75 in December, and remained around 60-70 until the end of production. The last 46 SPGs were built in May of 1944, when BMM switched to production of the Jagdpanzer 38(t).

Unlike its predecessor, the Panzerjäger 38 was primarily used by infantry divisions. In part, this was because the tank units were already saturated with vehicles of this class. These SPGs were only given to tank divisions in September of 1943. Shipments were erratic, partially due to the fact that vehicles were delivered as a part of reinforcements.

This is how the tarp was affixed on the Panzerjäger 38.

The new SPGs appeared on the front lines towards the fall of 1943. Their characteristics differed little from those of the previous tank destroyers on the Pz38(t) chassis, and the reviews were also similar as a result. Most complaints had to do with the driver's station. Visibility left much to be desired, and water got inside during rain. The tight layout of the SPG caused complaints regarding the difficulty of service.

Welded casemates were introduced in November of 1943.

Another issue had to do with improper use of the SPGs. One often hears about how SPGs were used like tanks in the Red Army. German infantry often treated their SPGs in the same way. Considering the large silhouette and thin armour, it's not hard to predict the results of this use. Nevertheless, there were quite a few vehicles still in service by the end of the war. 277 were in service as of December 30th, 1944, plus 62 in repairs. 118 remained on March 15th, 1945, plus 51 in repairs. Of this number, only 4 Panzerjäger 38 remain to this day.

The chassis was also welded.

The concept of a light self propelled gun mount proved itself. However, it's hard to claim that German and Czech engineers managed to find an optimal solution. The aim to retain the chassis without serious changes led to a number of serious drawbacks in even the reworked design.

The SU-76M, the closest Soviet analogue, was much better. This vehicle also used light tank components, but the chassis was designed nearly from scratch, with the requirements of an SPG in mind. Soviet designers ended up with a vehicle that was inferior to the Panzerjäger 38 in penetration and top speed, but better in every other respect. The SU-76M was lower, more stable during firing, had a roomier fighting compartment, and the visibility of the driver was better. In addition, the Soviet vehicle was much simpler to service.



Prototype Problems

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"To the GABTU Tank Directorate
Chief of the 4th Department, Engineer-Major F.A. Nenarokov
Moscow, 2 Red Square, NKO building

RE: work of Savin's group on designing an AA gun for a tank.

The anniversary of our design group is July 3rd. Working alongside you, with joint efforts, we managed to obtain a model of a mount with a cannon and a machinegun by September 8th, 1941.

On September 14th, 1941, we composed a letter for Ya.N. Fedorenko to deliver to the Council of Commissars with a request to build a prototype at the factories of the People's Commissariat of Medium Machinebuilding (including NATI), but the group was moved to factory #174 in Chkalov.

I reported to you in letter #128-14.01-42 on work performed up to January 15th, 1942. Presumably, you are also aware of letters addressed to Major-General Ya.N. Fedorenko (#136-15.01-41) and Major-General B.M. Korobkov (#863-1.7.02-42), as I received letter #709196 written on January 23rd, 1942, from B.M. Korobkov, in response to letter #74 that I sent on January 8th to General I.V. Grymzin.

In short, factory #174 had every opportunity to produce not one, but several variants of mechanisms for the AA gun (we had a ZIK-37 gun in our possession from the Donguzskaya proving grounds), but the factory did not wish to perform this work, despite comrade G.V. Gudkov's interest in the topic.

Chief engineer A.S. Zasovenko, true to himself, did nothing in the span of six months (October-April).

Keeping in mind the NKTP's orders to "adapt the mount to the T-34", my senior engineer-designer I.I. Mozhayev spent three months (February-April) at factory #183 in Nizhniy Tagil. The T-34's turret was heavier than the T-50's, which all of our blueprints were designed around, and the traverse drive had to be redesigned (again, maximizing the number of components already in production). The layout was exactly the same and remained in the same cast production turret.

As a result, we obtained a decent solution, from our point of view, which allowed the gun to be elevated to 60-70 degrees in 1 second and a traverse rate of 30-40 degrees per second. The trigger action is instant, as one cannot hit a dive bomber any other way.

Like everyone, factory #183 had its priorities, work that was vitally important, and the subject of an AA gun was a foreign and unwanted intrusion. We were given no people or materials. The issue became worse when the factory began expediting vehicles known to you.

Presently, we are in our fourth location! We changed places four times in a year! This does not help matters. In addition, at this factory, after 1.5 months of our presence, they had a meeting on May 22nd, threw out our drawing boards, and knocked off all of the equipment we had set up, even through they promised S.A. Ginzburg on May 19th that they would help up and to S.A. Afonin on April 7th that the SPG would be built in metal soon. We were called up, presumably, to design an SPG, but we are building an AA tank. The only thing we could offer was to test the mount on their SPG, with the expectation that it could be used on the T-34 and other vehicles without any changes.

Finally, we could install the ZIK-37 on a T-60 or 70 turret ring (it would be tight for two, but perfect for one, given the rate of fire of the gun and 12 round magazines). They did not wish to accept a light AA tank, and began working on an SPG with the ZIK-37 and five men, like on the special SPG. The amount of road wheels will not allow this with the 950 kg gun, but they do not wish to install the 300 kg gun, since it's our design. Our interests diverged, and they did not give us any people. In the experimental department there are also almost no people.

We were happy when comrade K.M. Vasilevskiy familiarised himself with our work and its results (the PT-12 MShZ device). He made valuable comments, which we immediately implemented.

There are no more locations left in the tank industry. We need a reliable base that would be interested in producing the vehicle, provide independence to the head of the design group without hovering over him. If what I was proposing last year was done, then the vehicle would be in production that year.

Factories #20, #69, and others did their job well. As they do not build tanks, I turn to you. Please put us in contact with a tank repair base that could give us a T-50 or a T-34 chassis. We can find a turret or make our own. There are plenty of bases near Moscow and closer to the front. We can use many parts produced by factory #183 (the list is enclosed). I assure you and High Command that this is the only way it can be done. Financing the group is a waste of time, as the GAU finances SPGs. There are many open spaces in Moscow, for instance at factory #37, NATI, and others. There can be no other way that this vehicle will be built. The group could not work intensively since September, for almost nine months! We could have done a lot of good in this time if we had our own base.

Project and group supervisor I. Savin.
June 26th, 1942"

Yuri Pasholok also provides a blueprint of Savin's turret for the T-34.

CAMD RF 38-11355-668 p. 13

F-32 in A-34

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"Secret

To the ABTU Chief, Corps Commander Pavlov
NKO House, 2 Red Square, Moscow

On the issue of: production of armour and assembly of A-34 hull and turret.

The armour for the A-34 is ready, both for the hull and the turret. The hull is in the finishing stages of assembly, the turret assembly will begin on December 22nd.

According to your instructions, the turret was built to take the L-11 gun. We have learned that you intend to install the F-32 gun into the production vehicle. To this day, our factory does not have a complete set of F-32 blueprints or the gun itself. This does not permit us to design the mount for an F-32 gun in the A-34 or create working blueprints for the aforementioned mount. 

I ask you to issue instructions to send a full set of F-32 blueprints to our factory, and immediately give us at least one gun. Delays in sending the blueprints and the gun will make it much more difficult to put the A-34 with an F-32 gun into production.

Factory director Maksarev
Chief designer M.I. Koshkin
December 20th, 1939"

Handwritten notes on the document read:

"To comrade Panov: figure out this issue and take measures to ensure no production delays. I. Rogachev, December 31st."

"A letter regarding the F-32 was sent by the 4th department. No additional blueprints will be sent. A copy was sent to the military representative at #183 and the chief engineer of factory #183, comrade Makhonin, familiarized himself with the issue. I.G. Panov, January 5th, 1940"

Canadian Ratte

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The German 1000 ton Ratte tank is a pretty well known device, and similar monstrosities described by well-meaning Soviet citizens volunteering their ideas. Turns out, the Western Allies were not immune from these flights of fancy. This suggestion was forwarded by a pretty high ranking official: than Sir Howard d'Egville. The description begins very promisingly: "...this vehicle, while not actually a tank, is of such capacity that it would be equal, in both offensive and defense power, to a considerable number of tanks." The armour is fairly reasonable at 5 inches (127 mm), but the armament is "of great striking power, including 4 inch naval guns". The vehicle would be transported in section, and if a section was knocked out, it would be removed and replaced. While not going into details on the design, d'Egville wanted a mockup built in Canada, and then the parts manufactured in several places, to preserve secrecy.


In reply, he received a rather ruthless evaluation: "it is highly unlikely that there is anything of practical value in the idea".

Mauser Sniper Rifle

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"5. Determining the combat characteristics of the German sniper rifle

The results of determining the muzzle velocity of the German sniper rifle are included in attachment #4, where you can see that the muzzle velocity of the Mauser rifle #6448 is 764 m/s.

The results of the precision and accuracy of the German sniper rifle with open and optical sights are included in attachment #5. Here are the average results.


With open sights
With optical sights
Dispersion radii, cm
Deviation from point of aiming, cm
Dispersion radii, cm
Deviation from point of aiming, cm
100%
50%
Vertical
Horizontal
100%
50%
Vertical
Horizontal
100
9.5
3.6
+12.5
+0.7
9.4
3.9
+1.9
-20.2
300
28.3
15.0
-17.8
+14.0
33.3
15.3
-56.7
-48.0
600
47.3
25.7
-56.3
+47.7
61.0
25.3
-165.0
-101.7

Last Request

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"Report on the requests of imported armoured vehicles as a part of the 5th protocol
  1. M4A2 tanks: 5000
  2. T26 tanks: 1000
  3. Harley-Davidson motorcycles (preferably with a sidecar): 6000
  4. Mobile armoured vehicle workshops (preferably 50% with machining equipment and diesel generators): 1200
  5. Diamond-T transporters: 750
  6. Beo transporters: 350
  7. 8 ton automotive cranes: 40
  8. 10-15 ton automotive cranes: 285
  9. Portable 150 atm compressors: 200
  10. M15 SPAAGs: 2000
  11. M17 SPAAGs: 2000
  12. Spare parts: 20,000 tons

Deputy Chief of the Main Armour Directorate of the Red Army, Lieutenant-General of the Tank Service, Lebedev
March 15th, 1945"

Via Yuri Pasholok

Pershing: Heavy by Necessity

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The British Churchill tank was the only one supplied to the USSR by the Western Allies en masse. The US had bad luck with heavy tanks. Work on the Heavy Tank M6 hit a dead end. Nevertheless, heavy tanks did arrive in the American army by the end of the war. These were Heavy Tanks T26E3, standardized as M26 Pershing. However, the T26E3 was rather arbitrarily classified as heavy. In practice, this was a medium tank. Only its mass made it a heavy, and even then, it returned to medium after the war. This article is dedicated to the trials of the T26E3 in the USSR, during which it was compared to heavy tanks.

On the schedule

The T20/T23 tank program was launched in the US in mid-1942. These tanks were radically different from any other American design. Instead of a front transmission, which Harry Knox copied from the British Vickers Mk.E tank, these tanks had a classical layout with a rear transmission. The design of American tanks was gradually evolving, in no small part thanks to the study of foreign tanks. The USSR helped out here. The T-34 and KV-1 at the very least influenced the tanks of this family. Primarily, the influence touched the torsion bar suspension to replace VVSS. Even though this suspension was far from the first to be tried, it won out in the end.

The torsion bar equipped Medium Tank T23E3 was supposed to be standardized as the M27, but the electric transmission doomed this tank. Nevertheless, a part of this tank went into production. The turret was installed onto a Medium Tank M4 chassis, which noticeably improved the vehicle's effectiveness.

Heavy Tank T26E1, Aberdeen Proving Grounds, January 1945.

Further development focused on the T25 and T26 medium tanks, which received powerful 90 mm T7 (later M3) guns. The Medium Tank T26 was considered the optimal variant. However, during development, its mass increased to 41.9 tons. Because of this, the version of the tank that was put into production, the T26E3, was called a heavy tank. To compare, the American T23 medium tank weighed 34 tons. In a way, the American designers repeated the "success" of MAN's designers, who started developing the Panther in the 30 ton weight class and ended up with a 45 ton tank.

The Soviet military knew little about this evolution of the American tank. They first discovered the Medium Tank T20/T23 program in the summer of 1943, during a visit to the General Motors proving grounds. The meeting with this prospective tank was unplanned, a result of oversharing by Quentin Berg, one of the creators of the GMC M10 and GMC T70 (M18).

A request from the Red Army Main Armour Directorate for American military vehicles in 1945. As you can see, the M26 is present in large amounts.

More complete information began to come in by mid-1944. Soviet specialists already knew that the prospective tanks are available in various variants, differing in suspension and other elements. It was also known that the torsion bar suspension was not deemed optimal at first. According to information that was obtained, HVSS showed comparable results, which made the American waver. The Soviet military also knew that the Medium Tank T26 and Medium Tank T26E1 were upgraded to heavy tanks on July 25th, 1944. Production numbers were also on hand. According to them, the T23 would be the most numerous of the medium tanks, even though the T23 program was winding down in favour of the T25 or T26.

The manifest of the SS August Belmont, which brought the new American tank, among other cargo.

It was clear that the Americans gave the T26 priority by the end of 1944. According to information received on January 13th, 1945, production of 192 tanks of this type was planned during the first two months of 1945. The index M26 was already used at this point, applied to the T26E1. In reality, another vehicle was called M26, the T26E3, but that did not happen until March of 1945. Overall, 450 vehicles were planned for the first quarter of 1945, and 6000 during the entire year. It is not surprising that 1000 T26 and 5000 M4A2 tanks were included into the Soviet Lend Lease requests. The Americans were not opposed to these deliveries, provided that their army received sufficient tanks first. However, nobody opposed sending one M26 (T26E3) to the USSR.

Technically experimentall

A Heavy Tank T26E3 with registration number 30119961 was sent to the USSR for study. This was a production vehicle, but it was referred to as experimental by Soviet specialists. This was because the T26E1 initially held the index M26. The tank was loaded aboard the SS August Belmont, which also carried prime movers and 13 M4A2E8 medium tanks. The transport was a part of convoy JW-66, which set out for Murmanck on April 16th, 1945 and arrived on the 25th. Unlike JW-65, this convoy took no losses.

Heavy Tank T26E3 at the NIBT proving grounds, summer of 1945.

The tank arrived in Kubinka towards the end of May. A trials program was composed, which included a study of the vehicle, mobility tests, and trials of the armament. As it often happened, an issue arose with the last item. The tank arrived with no ammunition. Even though the USSR had M1 AA guns, whose ammunition was compatible with the M3 90 mm gun, some time was needed to receive them. Complaints about missing ammunition were lodged on May 24th. Considering that trials were completely by July, the issue was solved quickly.

View from the right. The tank is clearly distinct from its predecessors.

Traditionally for these trials, they began with a study of the tank. This process was made easier due to the large number of technical documents that arrived with it, including a manual for the tank and its gun. Two technical descriptions of the vehicle were composed: a brief one, included in the report, and a full one.

A reworked layout allowed the height to remain at the level of a regular M4A2.

It's easy to explain the high degree of interest towards the T26E3. First of all, this was the first American mass produced heavy tank, even if it was only heavy by mass. Second, the layout was radically different from that of the existing American medium and heavy tanks, as was the layout of all T20 tanks. The layout of the Vickers Mk.E was gone, and the transmission migrated to the rear. The Americans reached this idea in 1942. Funnily enough, a year later, Heinrich Kniepkamp decided to use the exact same concept on the E-50, E-75, and other E-series vehicles. The use of the classical layout allowed the T26E3 to become 20 cm lower than the M4A2(76)W. Its armour was thicker, and a turret with more powerful armament was installed.

Looking from behind, the engine compartment hatches are visible.

NIBT proving grounds specialists guessed that the design of the tank's components was close to that of the GMC T70. This was partially true, especially the suspension. The Americans tested their torsion bar suspension on the T70. The degree of resemblance of the T26E3 was not as high as that of the T20E3 and T23E3, which used the same track links, road wheels, and drive sprockets. It is easy to explain these similarities: all of these vehicles were designed at the Tank-Automotive Center in Detroit. The idler adjustment system that allowed the tracks to keep tight also migrated from the SPG to the tank, albeit with some changes.

Overall diagram of the engine compartment.

The layout of the components in the engine compartment was deemed most interesting. The engine and transmission bays were separated with a block, on which the cooling system was installed. The testers remarked on the convenient access to components for service. The engine and transmission were joined into a single unit. This made it easier to install them into the compartment. However, this kind of solution had its drawbacks. First, the mass of the assembly was over two tons, which made it hard to remove in the field. Second, it was impossible to remove components individually, which also made field repairs difficult.

Engine and transmission assembly.

The transmission layout was another common factor between the T26E3 and GMC T70. Both vehicles had a Torqmatic Model 900-T gearbox and a torque converter. The gearbox, torque converted, and double differential were joined into one assembly. The biggest difference from the GMC T70 was that there was now a planetary speed reductor in between the engine and torque converter. It was put there for a good reason. Presumably, the issues experienced by the T70 off-road did not only plague Soviet testers. The installation of the reductor prevented the torque converter from slipping.

T26E3 transmission diagram.

A significant difference was the layout of the driver's compartment. It became much roomier after the transmission was moved to the rear. In addition, the driving controls were duplicated, making the assistant driver live up to his name. The driver could also set his seat to one of four positions.

The armour of the tank did not impress Soviet testers. This was not enough armour for a heavy tank.

Overall, the driver's compartment offered comfortable controls and good visibility. However, there was one problem. In October of 1945, after mobility trials were performed, trials were held to compare the effort required to drive tanks. Turning the tank in first gear at a minimum radius took 35 kg of effort on the right lever. To turn left smoothly, 32 kg of effort was required. Only the IS-3 needed greater strength to drive, although the M4A2(76)W was not far behind.

Visibility from the driver's compartment.

The design of the hull caused mixed feelings in the Soviet engineers. This was largely caused by the fact that the tank was branded as a heavy. The design of the hull that combined rolled and cast components was interesting. Its benefits included large hatches that made it easier to access components, as well as internal bulkheads, which made the hull more rigid. The biggest drawback was 101.6 mm of armour in the front. This was not enough for a heavy tank in 1945. Even protection of Soviet medium tanks that were being tested at the time was better. Another downside was the fan cap between the driver and his assistant. The final drive casings that protruded from the hull were also deemed a bad decision. There was a significant risk to damage the final drives by hitting mines or obstacles.

Fighting compartment visibility diagram. 

The turret also did not boast exceptional armour, with the same 101.6 mm in front. Its design was a logical progression from the T23 turret, which was also used on the M4A2(76)W. A large bustle housed the radio equipment freely. Traditionally for American tanks, the visibility from the turret was good. Despite the enlarged turret, the Soviet testers deemed the commander's station somewhat cramped. However, the gunner's station was very comfortable. The gun aiming mechanisms were well designed. Trials showed that traversing the turret all the way around took 100 second by hand or 17 seconds using the powered traverse.

Ammunition racks on the floor of the fighting compartment.

One of the few complaints about the gunner's station was caused by the sights. They only had scales for armour piercing shells. It turned out to be quite inconvenient to fire HE shells and the coaxial machinegun with them. There were also complaints about low magnification. The loader's station was also well designed, but not without fault. The ammunition racks on the floor forced the loader to make additional movements, which reduced the rate of fire.

Soft and hungry going

Initially, it was planned that the tank would go through the standard cycle of mobility trials, including driving on a paved highway, dirt roads, and off-road. An order from the head of the Main Armour Directorate of the Red Army, General Fedorenko, came in right before the trials began, instructing the testers to shorten the program. As a result, the 1000 km distance was shortened to 500 km. Trials to determine the top speed, highway, and off-road driving were cancelled.

T26E3 during mobility trials.

Driving took place only on badly smashed up forest roads. This impacted the average speed, which was only 18.9 kph. It was deemed good, since it would clearly be higher in better conditions. Comparisons were made with other tanks that were tested on the same roads at about the same time. These were, primarily, the T-44 and IS-3 tanks. The IS-3's average speed in these conditions was 14.6 kph, and average technical speed was 11.1 kph. The T-44 drove at 17.5 kph and 15.5 kph respectively. A comparison with the American M4A4 medium tank was also made, which had average speeds of 16.5 and 14.8 kph. A Panther tank, the closest analogue of the Pershing, was also tested. Its speeds were 15.8 and 11.4 kph respectively.

The American heavy tank easily climbs up a prolonged slope.

The presence of a torque converted was considered a big plus. It gave the tank significant power, which was especially noticeable on slopes. The tank gained speed quickly. The driving was quite smooth, thanks to the torsion bar suspension and telescoping shock absorbers. The suspension absorbed small bumps, which led to an increase in average speed. The vehicle accelerated to 30 kph over 15 seconds, having travelled 68 meters.

A 31 degree descent did not cause any problems.

The cost for using a torque converter was record fuel consumption. The T26E3 consumed 585 L of fuel for 100 km of driving. In these conditions the IS-3 consumed 373 L of fuel, and the T-44 consumed 378 L. However, we must remember that the IS-3 and T-44 had diesel engines. The gasoline powered M4A4 and Panther consumed 503 and 595 L respectively. The testers explained the high fuel consumption with the low efficiency of the torque converter and the fact that the engine constantly worked at maximum output.

The GMC T70 had similar issues, but it also had significant issues with overcoming obstacles. Startup trials of the T26E3 showed that the installation of a planetary reductor largely solved these issues.

Driving at a tilt of 35 degrees.

The improved transmission affected the tank's performance on climbing and descending grades, as well as driving at an angle. It turned out that, as the instructions specified, the tank successfully drove at a tilt of 31-32 degrees. The maximum angle of descent, 31 degrees, was also the same as in the manual. The tank managed to overcome a 35 degree slope. The tank could also tow an IS-2 with no issues, however the fuel expenditure rose to 160 L per hour.

The biggest defect was the destruction of road wheel rims.

The tank demonstrated good mobility during trials. The only engine trouble was experienced on the 126th kilometer of the trials, and only then because the fan belt roller was installed incorrectly. The only transmission trouble happened on the 54th kilometer, when an oil pump roller broke. After it was repaired it broke once more, along the welding seam. It was then replaced by a newly manufactured part. The biggest issues were with the suspension. Significant wear of the drive sprocket teeth was observed. The rim of one of the road wheels was destroyed towards the end of the trials. Partial destruction of other road wheel rims was noticed later.

Armour piercing shells M77 (left) and M82.

The next stage was testing of the armament. The Heavy Tank T26E3 carried the M3 90 mm gun, which had the same ballistics as the M1 AA gun. By the time the trials began, both types of armour piercing shells were available, as well as HE shells. Trials showed a rate of fire of 6-7 RPM. Firing from short stops allowed for one shot in 11 seconds. Such a big time between shots was the result of significant oscillations of the tank after stopping. Precision during firing from short stops was deemed good.

The M82 shell demonstrated less impressive results.

While driving at a speed of 12-13 kph, a hit rate of 40-50% was attained, and 10-20% at 24-26 kph. Unlike the M4A2(76)W, the tank had no gyroscopic stabilizer, which impacted the results of the trials. The stability of the hull during firing was deemed satisfactory.

The situation with fumes in the fighting compartment was far from ideal. It turned out that the concentration of fumes was far in excess of acceptable norms. The concentration decreased when the fan was turned on, but was still very high.

Marks on the Tiger's armour after being shot from 1300 meters.

The results of the penetration trials were also mixed. Two types of shells were used: M77 without a cap, and M82 APCBC. Individual plates from a Tiger tank, installed at various angles, were used as targets. Trials showed that the M77 shell can penetrate an 82 mm thick plate at 50 degrees from 1300 meters. This result is similar to the performance of the German 88 mm KwK 36. The result was good, but German tanks, especially heavy ones, had much more powerful guns. The American gun slightly surpassed the Soviet 85 mm S-53 gun, but was worse than the 100 mm D-10.

Serious underestimation

The undeserved status of a heavy tank and the raised expectations resulted in a rather harsh verdict. While recognizing a number of positive qualities, the testers deemed that the T26E3 was not up to modern standards. However, the T26E3 was a medium tank, not a heavy one. The conclusion that this tank was experimental was also a big mistake. The Heavy Tank T26E3 successfully fought during the last months of WWII. However, the verdict about its weak armour was confirmed.

Five years later, the M26 Pershing was fighting in Korea, now as a medium tank. Its opponent here was the T-34-85, which it certainly surpassed. Nevertheless, it is hard to blame the testers for their evaluation of the American tank. It was considered heavy, and that meant that it was compared to German heavy tanks and the IS-3. The tank that was sent to the USSR did not survive to this day. It was sent to Leningrad after the trials, and it did not return.

IS-3, Take One

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"Report on experimental work at factory #100 for the first 10 days of June, 1943

Most effort at the factory was directed towards production and assembly of IS-3 components according to altered blueprints and continuation of factory trials of IS-1 and IS-2 tanks, bringing the total distance travelled to 2000 km.

Production and assembly of IS-3 components
  1. The factory #100 production plant received altered blueprints on May 25th, 1943.
  2. All components are in production aside from those that cannot be produced at factory #100: the hull, F-85 gun mount, turret, commander's cupola. The aforementioned parts are being produced at factory #200. The final drive and a portion of the drive sprocket are being produced at the Kirov factory.
  3. Most components for one vehicle have been completed and are being finished at factory #100, with the exception of the cooling fan, ammunition racks, and individual parts of other assemblies.
  4. The assembly of the drive sprocket and lower suspension has started.
  5. The gearshift gate, idler with tension mechanism, radiator, main friction clutch, speedometer control rod, planetary turning mechanism, gearbox, control rods, and brake are assembled.
  6. Casting and forging work is finished.
  7. Assembly of the hull and turret at factory #200 is being delayed due to organizational reasons and production issues. Factory #200 promises to complete assembly by June 15th, 1943.
  8. F-85 artillery systems have not yet been received.
The Kirov factory, which is scheduled to produce two IS-3 tanks, is receiving three sets of parts (one set to be used for spares)."


T-45

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"To Lieutenant-General Fedorenko

Factory #37 in Sverdlovsk installed a 45 mm gun on the T-60 tank without widening the turret ring, but in a new turret. The positioning is the same as on the T-70. 

The loading conditions are the same as on the T-70.

The weight of the vehicle increased by approximately 400 kg. Ground pressure increased by 0.03. 

Top speed dropped by 5-8 kph (used to be 45 kph, now 38-40 kph). Range not affected.

Ammunition capacity:
  • Shells: 66
  • Machinegun rounds: 945 (same as on the T-70)
Armour:
  • Lower front plate: 35 mm
  • Upper front plate: 30 mm
Others without change, same as on T-70.

I inspected the tank myself.

Gave directions to move the trunnions and commander's seat carrier, move the machinegun to be next to the cannon, and the sight on the left. The factory agreed, and will telegraph you, asking to approve the decision. The factory guarantees delivery according to the schedule assigned by the government. This change will free the factory from producing the T-70, thus avoiding a drop in production.

I consider the proposition to be tempting, since the commander's conditions will be no worse than on the T-70.

I ask for a commission to perform the trials, as follows:

Chair: Chief of the Ural Military District Armoured Forces, Lieutenant Colonel Yevdokimov
Members:
  1. Commander of the 106th Tank Brigade
  2. Senior military representative at factory #37, Engineer-Major Koptsov
  3. Senior Engineer of the 5th Department of the BTU, Engineer-Major Goryushkin
  4. Assistant to the Chief of the 4th Department of the BTU, Engineer-Captain Yezernitskiy
  5. Senior designer of factory #37, comrade Popov
  6. Representative of the People's Commissariat of Tank Production (your choice)
I ask for your directions. I am at the Chelyabinsk factory.

Engineer-Colonel Afonin

May 8th, 1942"

Heavy Trophy

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The German heavy Tiger tank left a mark on tank building worldwide. Even though propaganda and memoirs are largely to blame for its fame, the Tiger did really have nearly no competition on the battlefield among the tanks of the Allies. It's not surprising that the tank was thoroughly studied in the USSR, USA, and Great Britain. This article tells the story of how Tiger tanks were studied in the USSR and what conclusions were made, as well as the use of these tanks in the Red Army.

Present from Leningrad

The German tank first went into battle on August 29th, 1942, during the Sinyavino operation. These were Tigers from the 502nd Heavy Tank Battalion. Their combat debut was not particularly impressive. The swampy terrain at Mga where the battalion fought was far from ideal. Interestingly enough, another 502nd heavy tank battalion fought nearby. This was the Soviet 502nd Heavy Flamethrower Tank Battalion, equipped with KV-8 tanks. Mere kilometers separated the two battalions.

Red Armymen study the captured German heavy tank. January 18th, 1943.

The combat debut of these new tanks went unnoticed by the Red Army. The GABTU learned about the Pz.Kpfw.VI tank in the fall of 1942, but the information came from the British. On November 9th, 1942, the British Military Mission in the USSR passed on information about new German tanks and SPGs. Among it was a list of new vehicles, captured by the British in North Africa. The document, dated October 7th, 1942, mentioned tanks such as the VK 9.01 (PzII Ausf. G), PzI Ausf. C, and VK 16.01 (PzII Ausf. J).

Finally, the document listed the PzVI. The British did not know what kind of tank this was, and asked the GABTU to share any information. The British only guessed that this tank would be heavier than the PzIII and PzIV. However, the Allied did not have to wait for long. The 501st Heavy Tank Battalion arrived in Tunisia in late November, 1942. The Americans were the first to come under fire from these heavy tanks.

The road wheel rim on the ground suggests that the tank had issues with more than the engine.

The 502nd battalion lay low after the failed debut at Mga. It returned to battle on January 13th, 1943. Operation "Spark" began a day before, with the aim of penetrating the blockade of Leningrad. The battalion suffered its first losses on January 17th, losing tanks #250003 and #250006. One of them became bogged down, the other took a hit to the turret. The transmission on the second tank also broke down. Both tanks were blown up.

It's worth mentioning that the 502nd Heavy Tank Battalion did not consist of Tigers alone. About a third of the tanks were PzIII Ausf. L, and about as many PzIII Ausf. N. 4 PzIIIs from the 1st company of the battalion dug in around Workers' Village #5. They were opposed by, in part, T-60 tanks from the 61st Tank Brigade. This brigade was fully armed with T-60 tanks produced at factory #37. The brigade received T-70 tanks during the battle, but they did not take part in the fighting described here. The brigade also had a battalion of BA-10 armoured cars, which was assaulting Shlisselburg. 

The winter camouflage and elephant insignia can be seen.

Knowing that the situation around Workers' Village #5 was growing dire, battalion command sent one PzIII and two Tigers as reinforcements on January 17th (the latter, however, arrived later). With reinforcements in hand, the Germans decided to attempt reconnaissance in force. Early morning on January 18th, three PzIII tanks took off, accompanied by infantry. By pure luck, the 61st Tank Brigade decided to perform reconnaissance as well. A group of skiers was supported by one T-60 tank, commanded by Lieutenant L.I. Osatyuk. The two groups met unexpectedly at around 7:30 am. Of course, the light T-60 could do little against the PzIII, and so Osatyuk ordered to his driver, Starshina I.M. Makarenkov: "Vanya, dance!"

Maneuvering in his tank, Makarenkov evaded his pursuers. Together with Osatyuk, he lured the Germans in front of an anti-tank gun battery. As a result, two PzIII tanks were destroyed, and the one that got away didn't get far. This was the first in a series of unfortunate events that plagued the Germans at Workers' Village #5. Having disposed of his pursuers, Osatyuk opened fire on enemy infantry, and then the Soviet assault began. Five T-60 tanks were knocked out and one burned up. However, neighbouring brigades supported the offensive, and the Germans were forces to reveal their line of defense and suffered a defeat. Workers' Village #5 was taken by noon on January 18th.

Presumably, an attempt was made to tow the tank away. The Red Army's rapid offensive did not allow the evacuation to proceed.

The Red Army captured an abandoned Tiger, turret number 121, serial number 250004. According to German data, its engine and radiator were broken. The Soviet description agrees with this assessment. The tank was undergoing repairs when it was captured.

This was not the end of the 502nd battalion's streak. Unaware that Workers' Village #5 was captured, the commander's tank with turret number 100 and serial number 250009 approached the settlement. Shortly before reaching it, the tank drove off the road and became bogged down in a peat bog. The crew left the tank and walked towards the settlement. Upon realising that it was no longer in German hands, they decided to withdraw. That is how the Red Army obtained two Tigers, one of which was undamaged. The Red Army also obtained documents, including a brief instruction manual and the waybill.

Fearsome opponent

Operation "Spark" resulted in a penetration of the German defenses. The success was relatively small, but it allowed supplies to reach the city by means other than the Road of Life. The first echelon with supplies arrived on February 7th. The Red Army's success defined the fate of the German tanks. Thanks to the breach in the German lines, it was possible to bring them to the "mainland". However, the study of the tanks began almost right after they were captured. A technical description was ready by the end of January. In parallel, the documents captured with the tanks were translated. Due to the rush and a lack of precise data, the description was far from ideal. For example, the mass was estimated at 75-80 tons, which is significantly higher than in reality. The armour thickness was also incorrect.

Tiger #121, NIBT proving grounds, April 1943.

Initially, the tanks were called "HENSCHEL captured tank". Later, the index T-VI was used. The Leningrad Front captured at least two additional tanks. Correspondence lists two tanks in addition to tank #100. One of them was captured completely burned up, the other knocked out and partially burned. This tank was the donor for the repair of tank #100. Pieces of armour were also cut out for study. Tank #100 was sent to Kubinka for study, but that was later. Tank #121 was sent to Kubinka first.

The same tank from the right. The winter camouflage was washed away.

The new tanks were very interesting. By this time, the tanks were actively being used both on the Eastern Front and in Africa. The first massed use of these tanks happened at Kharkov, which made a significant contribution to the Soviet defeat there. Around the same time, these tanks were fighting in Tunisia, inflicting heavy losses on the British and Americans. The British were very forthcoming with information on the new German tank. On April 5th, 1943, the Soviets received a British report on the trials of a 6-pounder gun versus a "German Mk.VI tank". These trials took place in late March. 5 shells out of 10 penetrated the front plate of the tank from 300 yards.

After the camouflage was washed off the turret number became clearly visible.

Tanks #100 and #121 were already at the NIBT proving grounds by April of 1943. It was decided that one tank will be shot up, the other will be used to evaluate the armour of Soviet tanks. Tank #100 was the lucky one. As for tank #121, it had its equipment removed and prepared for trials by April 25th.

The emblem of the 502nd Heavy Tank Battalion is visible on the front.

Trials took place from April 25th to April 30th, 1943. 13 cannons, 5 anti-tank rifles, the KB-30 anti-tank grenade, 2 types of anti-tank mines, and the 37 mm aircraft gun from a LAGG-3 were used. Of those, three weapons (the 107 mm M-60, 122 mm M-30, and 152 mm ML-20) managed not to hit the target, even though the weather was clear.

Results of shooting with the 45 mm gun. The subcaliber shell penetrated the armour from 200 meters.

The T-70 opened fire against the Tiger first. It was clear that firing at the 80 mm armour with the regular shell was pointless, so the tank used subcaliber ammunition. One shot from 200 meters penetrated successfully. From 350 meters, the 60 mm thick lower side could be penetrated. The model 1942 anti-tank gun showed similar results. Its armour piercing shell could not penetrate the upper side from even 100 meters, but the subcaliber shell penetrated from 350 meters.

The Tiger's armour was not a significant obstacle for the ZIS-2 and 6-pounder.

57 mm guns were next. Both the Soviet ZIS-2 and British 6-pounder showed similar results. The side could be penetrated from 800-1000 meters. As for the front armour, the ZIS-2 could not penetrate it from 500 meters. It was not fired from a closer distance, but all signs pointed to the fact that it would penetrate from about 300 meters. Data received from the British confirms this. The British anti-tank gun had a shorter barrel, but higher quality ammunition gave it comparable penetration.

Results of firing the American 75 mm M3 gun.

The American 75 mm M3 gun, installed in an M4A2 tank, also performed well. Two armour piercing shells were tested: M61 and M72. The M61 could penetrate the side from 400 meters, the M72 from 650 meters. As with the 6-pounder, a high quality of the ammunition was noted. The gun did not fire at the front plate. It is likely that the testers knew it would be a fruitless endeavour. 

The tank's armour was too much for the F-34, the main Soviet tank gun at the time.

The trials of the F-34 gun turned into a real fiasco. Not a single shot penetrated, not even from 200 meters. This was true for the AP, experimental subcaliber, and experimental HEAT shell. This was the main Soviet tank gun of this period!

Another 76 mm gun, the 3-K, fared better. The difference was not that great, however. The 3-K's shell could not penetrate the side of the turret from 500 meters. In other words, its performance was approximately equal to that of the 75 mm M3 gun with the M61 shell.

The 52-K 85 mm AA gun showed the best result among medium caliber guns. It's not surprising that it was chosen as the highest priority for arming heavy tanks and medium SPGs.

The 3-K was far from the most powerful gun in the Red Army's arsenal. In addition, it was not produced since 1940. It was replaced by the 85 mm 52-K AA gun. It was considered as a base for a tank gun since 1940, but for various reasons work never progressed past the experimental stage. Meanwhile, AA guns were successfully used in the anti-tank role. Trials showed that the GAU and GBTU were correct in considering the 52-K as a prospective tank gun. It shell could reliably penetrate the front from a kilometer, and the sides from about 1.5 kilometers.

The Tiger after being shot by the A-19.

The 122 mm A-19 corps gun proved even more effective. Unlike the 52-K, it was not considered as a tank gun before this. A gun with the ballistics of the 107 mm M-60 gun was considered, but as mentioned above it did not even hit the Tiger. As for the A-19, it hit, and how! The first shell passed through a breach in the front of the hull and penetrated the rear. The second hit the turret front and tore out a 58x23 cm chunk. The turret was torn off the turret ring and moved half a meter. After being shot at by the A-19, the Tiger, which was looking unwell at this point of the trials, turned into a heap of scrap metal.

The same tank from the front.

The trials were not finished here. The German tank had not only thick armour, but a powerful 88 mm gun. During trials of tank #121, its brother #100 was shooting at Soviet tanks. A T-34 and KV-1 were used as targets.

KV-1 after being shot by the 88 mm KwK 36 L/56.

The results of the trials were predictable. The KV-1's additional front armour did not help. The first shot from 1.5 kilometers partially tore off the applique armour, the second penetrated the front armour. The idea of lightening the KV-1 tank was correct. The KV-1S was more mobile, while both the KV-1S and the KV-1 were more or less equal targets for the Tiger.

The T-34 looked worse after a Tiger attack.

Trials of the T-34 were worse. The first shot that hit the turret displaced it from the turret ring. Further hits partially destroyed the upper front plate. To compare, the 85 mm 52-K gun was fired at the tank. From 1.5 km away, the penetration was similar to that of the German gun. This is not surprising, since the German and Soviet guns were relatives. The 76 mm 3-K gun, which the 52-K was developed from, was based on the same AA gun as the German Flak 18.

After the end of the trials, both tanks were taken to an exhibition at Gorky Park in Moscow. They remained on display there until 1948, after which they were scrapped. As for the conclusions, they were made immediately. It was clear that 76 mm guns were no longer sufficient, and had to be replaced. GKO decree #3289 "On improvement of armament of tanks and SPGs" was signed on May 5th, 1943. It was the starting point for the development of 85 mm tank and SPG guns.

The GAU launched this program even earlier. As of April 28th, 1943, factory #9 already had its orders. Work was also launched at the Central Artillery Design Bureau (TsAKB). Work on the SU-152 SPG with a 122 mm A-19 gun was already underway. This idea was first voiced in March of 1943, after the study of a captured Pz.Slf.V. Finally, in May of 1943, factory #9's design bureau received orders to develop a tank version of the A-19.

The Tiger's appearance only accelerated this work.

Vulnerability diagram composed as a result of the trials. The tank in the drawing is quite clearly Tiger #121.

Another result of the trials was the acceleration of work on the ZIS-2 anti-tank gun. Despite common rumours, this gun was not completely discarded, it was merely reworked. The issue was that this work was not progressing very quickly. The meeting with the Tiger changed these plans. Instead of the IS-1 gun, which had a shorter barrel and altered trails, a new gun was designed, effectively combining the ZIS-2's barrel with the ZIS-3's mount and oscillating part. The 57 mm ZIS-4 tank gun was revived. In addition, the TsAKB began working on the 76 mm S-54 tank gun, as well as a self propelled variant.

In other words, the GBTU and GAU did not sit still. SU-85 SPGs and KV-85 tanks entered production in August of 1943. Production of the ZIS-2 mod. 1943 began even earlier, in July of 1943.

Tigers in the Red Army

Even though the Tiger was first captured in January of 1943, their use in the Red Army was uncommon. There were several reasons for this. First, the Germans rarely left these tanks behind in usable condition, attempting to blow up tanks that could not be evacuated or repaired. Second, remember that there were not that many Tigers. In addition, Soviet tankers tried to destroy Tiger tanks, not disable them, as this guaranteed a high award. Keeping all this in mind, you will not be surprised to learn that the first captured Tiger was used towards the very end of 1943.

Taking inventory of captured tanks. Late 1944-early 1945.

The first crew that is confirmed to have used a Tiger in battle was the crew of Guards Lieutenant N.I. Revyakin from the 28th Guards Tank Brigade. A Tiger from the 501st Heavy Tank Battalion became bogged down in a swamp. Its crew fled, and the tank became a trophy. On the next day, the tank was enlisted into the 28th brigade. Revyakin was appointed as the commander because he had great experience in combat and awards: two Orders of the Patriotic War 1st Class and an Order of the Red Star. On January 5th, the tank went into battle with red stars on its turret and the personal name "Tiger". The tank's career was about the same as in German hands. It constantly needed repairs. A lack of spare parts complicated matters. Later on, the 28th Guards Tank Brigade acquired another Tiger.

Another instance of a Tiger being used happened on January 17th, 1944. Lieutenant A.S. Mnatsakanov's T-34 crew from the 220th Tank Brigade managed to capture a working Tiger mid-battle. Using this captured tank, Mnatsakanov destroyed an enemy column. For this battle, he was awarded the title of Hero of the Soviet Union.

A KV-1 prime mover tows a captured Tiger.

The situation changed by the spring of 1944. A number of operations supplied the Red Army with a plethora of Tiger tanks. For instance, the 61st Guards Tank Brigade captured two Tigers on March 6th, 1944, at Volochisk, and 13 Tigers and Panthers at Gusyatina on March 23rd. One more Tiger was captured on the 25th. The brigade made good use of its trophies. 3 Tiger tanks were listed as a part of its assets as of April 7th. However, they spent only a few days in action. Most likely these were Tigers from the 503rd Heavy Tank Battalion, famous for losing only one Tiger in the battles of late 1943-early 1944.

Vehicles of the 51st Independent Motorcycle Regiment, July 5th, 1944. Tigers were most widely used by this unit.

This story doesn't end here. The Tigers were sent away for repairs. It is not known where, but there are complaints in the correspondence of the GBTU during the spring of 1944 that there are not enough gun sights and other optics for repairs of enemy heavy tanks. It can be concluded that the tanks did end up in a repair shop. Some of them were sent back to the front at a later date.

Only one unit that received repaired Tigers has been established so far. This was the 51st Independent Motorcycle Regiment. Typically, a motorcycle regiment included 10 T-34s, but this regiment was special. It included a company of captured heavy tanks, consisting of 5 Tigers and 2 Panthers. They were all repaired at Soviet factories. By the start of the Lvov-Sandomierz offensive, the number of Tigers fell to 4. Periodically, 1-2 Tigers would be reported as needing repairs.

The regiment lost 6 T-34-85 tanks in a battle on July 21st, 1944. In return, the enemy lost 2 Tigers, 3 SPGs, and 2 APCs. It's possible that enemy Tigers were knocked out by fire from captured ones. In total, 7 Tigers were destroyed between July 20th and 22nd, at a cost of 7 T-34-85s. The 51st regiment received reinforcements after that. As of July 28th, it had 9 T-34-85s and 4 Tigers. Of the 4, 3 were in need of medium repairs, but were still in running condition. By August 19th, the regiment still had 3 Tigers. After that, the regiment was transferred to the NKVD to deal with OUN groups. The Tigers were taken away.

In total, one can list at least 10 captured Tigers that fought in various Soviet units.

KV-85 Turret Upgrade

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"To the Chief of the GBTU Tank Directorate, Major-General of the Tank Engineering Service, comrade Afonin

The senior military representative of the GBTU at the Kirov Factory, Engineer-Lieutenant-Colonel Markin reported the following to me on August 31st over radio, 1943 (via comrade Davidenko).

A number of mistakes were made in the KV-85 blueprints, which resulted in the following:
  1. Fuel tanks could not be installed (had to be manually trimmed to fit).
  2. It was impossible to install an assisting pump (a wobble pump was installed instead).
  3. A Vortox air filter was installed instead of a Multicyclone.
  4. The shutters cannot be installed.
  5. The elevation mechanism was shifted by 35 mm.
  6. The telescopic sight is obstructed.
  7. The machinegun mount is right up against the side of the casing.
  8. Factory #9 did not supply counterweights for the gun (old counterweights are used).
  9. The periscopic sight is obstructed by 15%.
  10. The elevation angle is reduced to 20 degrees, the depression angle is reduced to 3 degrees.
  11. The turning mechanism bed is tilted.
  12. No recoil guard is installed.
  13. The rain cover cannot be installed due to the incorrect shape of the gun mantlet.
  14. The ammunition racks are placed as convenient, instead of according to blueprints.
  15. Installation of electric equipment also had to be done improperly, as the blueprints have mistakes and a number of inconsistencies.
Details are sent over mail. I ordered that the blueprints be corrected immediately.

Continue the acceptance process only after defects have been corrected. On the six tanks that have already been built, correct the defects following the factories' proposals.

Chief of the 1st Departmetn of the GBTU TU, Engineer-Lieutenant-Colonel Yegorov."

Upgunned T-38 Trials

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"Results of trials of a T-38 tank armed with a ShVAK gun from March 15th to 29th, 1944

T-38 tank #4216 armed with a ShVAK gun converted at factory #105 on January 13th 1944 was presented for trials. The engine ran for 2 hours since the last medium repairs.

After arming it with the ShVAK gun, the tank's weight increased by 400 kg. The tank was tested at 100% of combat weight with a crew of 2 men.

The route and trial conditions are described in the attached journal. 910 km were travelled during the trials (402 km on a highway, 508 km on a dirt road, off-road, and over obstacles). The engine worked for 48 hours and 40 minutes.

As a result of the trials, it was concluded that:
  1. The tank has a range of 220 km on a highway with one load of fuel (90 kg).
  2. Due to the increase in mass, it takes a greater number of engine revolutions to begin moving in first gear, especially on uneven dirt roads.
  3. The running temperature of the transmission and suspension was normal during a 2 hour nonstop march and a 100 km march over 5 hours with three stops for inspection.
  4. Duel consumption while driving on paved roads, dirt roads, and cross-country at an air temperature of -10 degrees did not exceed the existing norm of 6 kg/hour.
  5. The increased mass of the turret negatively impacts the hand traverse. Due to the weight, it is no longer possible to turn the turret by hand when it is driving across terrain with a large amount of pits and bumps.
  6. The installation of the ShVAK gun did not impact the T-38 tank's ability to cross natural or artificial obstacles.
  7. Exterior inspection of the tank and disassembly of transmission and suspension components revealed complete technical function of the hull, transmission, and suspension. See the post-trial technical act.
Conclusions: trials of a T-38 tank armed with a ShVAK cannon showed that the increase in the turret weight did not impact the tank's combat or technical characteristics, aside from turret traverse. The T-38 tank is a combat-capable vehicle, useful in combat on cross-country terrain and firing from short stops. To fire on the move, a turret traverse motor must be installed.

Conversion of tanks to use the ShVAK gun continues.

Chief of the Usage Department of the UK of the Armoured and Motorized Forces of the Far East Front, Engineer-Major Poletskiy"

Sd.Kfz.222 Under Fire

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A while ago, I posted how German armour fared under fire in Soviet trials. Recently, I found information on a similar British test. This time it was a hatch from an Sd.Kfz.222 being fired upon, but the conclusions were largely the same: German armour is too brittle and has a tendency to flake and crack. The test plate broke into four large pieces under fire from the 15 mm Besa at a velocity matching a range of 1500 meters at an angle of 30 degrees. The quality of the armour was worse than British armour made to I.T.70 requirements.








M1 Carbine vs Mkb.42(H)

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The precision of the MKb 42(H) at ranges of 100, 300, and 500 meters is 1.5 times worse than that of the American M1 carbine.

In automatic fire, the precision of the MKb 42 (H) is unsatisfactory (a burst doesn't fall inside a 1.5 x 1.5 meter target at 100 meters).

The reliability of the automatic mechanism has not been determined.

The design of the sample is complex, but the widespread use of stamped parts deserves attention.

Via kris_reid.

PIAT: An Odd Fellow

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The British PIAT grenade launcher, a combination of a medieval crossbow and a modern HEAT grenade, became one of the more unusual examples in its class. Heavy and uncomfortable to use, the PIAT went through many fronts of the Second World War in the hands of Allied soldiers. However, its subsequent career was not long. The weapon did not survive competition from the simpler and more reliable RPG.

British infantry was armed with two types of anti-tank weapons at the start of WWII: the 13.97 mm Boys rifle and the No.68 rifle grenade. Experience in France showed that these weapons could defeat German light tanks, but were ineffective against the medium PzIII and PzIV. The army needed a new anti-tank weapon that was compact but still capable of sufficient penetration. In pursuit of this weapon, British engineers had to resort to some unusual methods.

History of creation

In 1930, Stewart Blacker, a young British officer, patented a light infantry support weapon that was a further development of a spigot mortar. These weapons were rather common in WWI, and fired shells with hollow tails that were inserted onto a spigot. In 1937, the Parnell aircraft company produced a prototype of Blacker's weapon, which was named "Arbalest". It took part in a tender for a light platoon level infantry support weapon, but lost out to the Stocks 51 mm mortar.

The German Blitzkrieg in France revived the interest in Blacker's weapon. Now it was no longer a weapon that fired a fragmentation grenade for anti-personnel use, but as an anti-tank weapon. In 1940, Blacker, already a Lieutenant Colonel, was appointed to the MD1, the "irregular warfare" section. The fruit of his work was the Blacker Bombard: a massive weapon serviced by three or four men that fired 9 kg HE bombs. The Blacker Bombard was approved for service and put into production in early 1941, but it was never used in real battle, as the maximum range was only 100 yards. A few thousand Blacker Bombards were transferred to the Home Guard, which was formed in anticipation of a German invasion of the British Isles.

Realizing that the Blacker Bombard was not what the army needed, attempts were made to reduce the size of the launcher and make it serviceable by one man. A prototype of a smaller bombard was ready by mid-1941. Thanks to a lighter HEAT projectile, the weapon was much more compact. Now it could be fired from the shoulder. This design included a "half-barrel" directing pipe. However, trials of the mini-bombard were disappointing. Misfires were common. Even the grenade did leave the weapon, the target still survived, as the fuse did not work even once. Major Millis Jeffris was tasked with further development. Taking the miniature bombard as a starting point, he quickly produced an improved design, initially called the "Jeffris Shoulder Gun", later renamed to PIAT (Projector, Infantry, Anti-Tank).

Overall view of the PIAT grenade launcher.

Design

The American bazooka, German Panzerschreck, and other RPGs all have a simple design: a tube, open from both ends, that has sights and a trigger attached to it, as well as additional equipment such as a protective shield or a bipod. The British PIAT was much more complicated. It consisted of a tube, 83 mm in diameter, which had a directing semi-tube in the front. The semi-automatic mechanism was housed inside the tube. From the front, the body of the launcher was covered by a cap with a spigot in the center. The grenade was placed upon the spigot during loading. The striker was contained inside the spigot. The striker was a hefty steel cylinder with a firing pin on the front. The rear of the striker was up against a spring, with a slot cut in it to lock in place. A butt with a rubber pad was attached to the rear of the body, and a trigger mechanism inside a rectangular guard to the bottom. The sights, consisting of a collapsible front sight and a rear sight, were attached to the left of the barrel. A bipod or telescoping monopod could be attached below.

A fully disassembled launcher.

How did the PIAT fire? The process was very similar to how a medieval crossbow was used, and consisted of two steps: the winding and the loading. The gunner turned the butt to unlock it, and, bracing against it with his feet, pulled the trigger guard (this required significant force). The spring compressed, and the striker retreated to the firing position. The grenade was then placed upon the spigot. The weapon was ready to fire.

Upon pressing the trigger, the striker was freed, and was launched forward, impacting the primer. The expanding gases propelled the grenade forward and recoiled the striker, which compressed the spring and locked in place. Subsequent shots could be fired after only inserting a new grenade. Because of this, the practical rate of fire of the PIAT was quite high: 8 RPM, compared to the American bazooka's 4-5 RPM.

Ammunition

The main type of ammunition was the Bomb H.E./A.T. In addition, three other types of grenades were used: the dummy Bomb Drill/A.T. used to practice loading, the single use Bomb Practice Inert/A.T. and the multi-use Shot Practice/A.T.

Drawing of a grenade for the PIAT.

The hull of the grenade was made from thin tin. A 340 g explosive charge was held in the front, with a HEAT cone. A ballistic cap contained the F.P. No.425 instant fuse. The impulse from the fuse was passed on by a detonation cord to the detonator in the center of the explosive charge. The rear of the grenade consisted of a tube with four stabilizer fins, protected by a ring. The tube contained a brass casing with a primer and 2.7 g of nitrocellulose gunpowder for launching the grenade. The projectile weighed 1.2 kg.

Grenades came from the factory with the launching charge already installed. The fuse came in a tin case attached to the stabilizer ring. Its slot was covered with a cork. Grenades were packed into a container made from three greased cardboard pipes. A 41x34.4x10.7 cm contained with three grenades weighed 6.4 kg. Three containers were packed in one wooden crate.

Service

The PIAT took a long time to develop, so it did not come in time to fight in North Africa. Production of the first batches began in August of 1942, and it was only issued in the middle of next year, right in time for the Allied landings in Sicily. 115,000 PIATs were made by 1944, and production continued until the end of the war (over 7.5 million grenades were made).

Loading training.

The PIAT quickly became the infantry's main anti-tank method. The infantry battalion TO&E distributed the PIATs in the following way:
  • Infantry company: 3
  • Reconnaissance platoon: 4
  • 3" mortar platoon: 3
  • 4.2" mortar platoon: 1
  • Machinegun platoon: 1
  • Quartermaster platoon: 3
One battalion had 21 PIATs in total.


A fully equipped PIAT operator.

The PIAT had no dedicated crews. All infantrymen trained with it. The commander of the company or platoon assigned PIAT crews directly before the battle. Even though the PIAT was developed to be serviced by just one soldier, practice showed that one man cannot carry the hefty launcher and ammunition at the same time. An ammunition loader was assigned to aid him, carrying two containers with grenades (six grenades in total). Gunners were instructed to open fire from as short a range as possible, as the maximum range of a PIAT was only 115 yards. The PIAT could also be fired indirectly. In this case the maximum range increased to 320 yards, but the precision left much to be desired.

The PIAT was used to support assault teams as well as to fight against armoured targets. The assault team manual suggested that 2-3 PIATs be assigned to each group. Of course, the grenades were powerless against stone walls, but they could suppress enemy positions in windows and portholes. British troops used the PIATs in this way during the Normandy landings. Sergeant Stanley Hollis received the Victoria Cross for the destruction of an enemy artillery position with one. There were also plenty of successful applications of the PIAT against armour. For example, during Operation Market Garden in September of 1944, British paratroopers destroyed several StuGs that attacked their positions.

PIAT from 2/10th Australian battalion, Balikpapan, July 1945.

The PIAT appeared on the Pacific theater of war in late 1943. The Australians called it PITA (Projector Infantry Tank Attack). The grenade launchers were issued to "jungle divisions", with one launcher per infantry platoon. The main target for the PIAT was not so much Japanese tanks, which were rather rare, but enemy strongholds. Sometimes the PIATs were used in their intended role. For instance, Private Ganja Lama of the 1st Battalion 7th Gurkha Regiment used his to great effect at the battle at Ningtouhonga on June 12th, 1944. When his company was pinned down by heavy fire, Lama crawled up to a range of 30 meters with his grenade launcher and destroyed two tanks. For this heroism, the brave soldier received Britain's greatest honour: the Victoria Cross.

The USSR received a thousand PIATs and 100,000 grenades, but details of their use are unknown. A large number of launchers was also dropped by parachute in occupied Europe. For instance, the Polish Armia Krajowa was sent 530 launchers and nearly 9000 grenades between September of 1943 and February of 1945. It is known that PIATs were used during the Warsaw Uprising, as well as by the French Maquis and Yugoslavian Partisans.

Warsaw resistance fighters from the "Czata 49" battalion with PIAT launchers.

The PIAT's post-war career was short. The British army abandoned it in 1951, replacing it with ENERGA rifle grenades and American M20 "Super Bazookas". The Australians continued to use the PIAT alongside the M1 Bazooka until the Korean War, but both weapons were quickly displaced by the Super Bazooka. Some number of PIATs fell into the hands of the Haganah and was used during the first Israeli-Arab War of 1948-1949. The IDF retained the PIAT until the late 1950s.

Haganah soldier with a PIAT.

Advantages and drawbacks

The Canadian army performed a questionnaire among its combat officers in 1944-45 to establish which infantry weapon was the most effective. The PIAT took first place of 31 weapons (the Bren gun came second). The officers' subjective feelings seemed to agree with operational research. 7% of enemy tanks knocked out in Normandy fell to the PIAT. To compare, ground attack aircraft were responsible for 6%. However, after German tanks and anti-tank guns began using HEAT shields in large quantities, this percentage began to decline.

The first warning bells rang during the fighting in Sicily. Complaints were made about the low precision and reliability of the PIAT grenades. Trials gave disappointing results: only 60% of the shots from 100 yards hit a stationary tank. A quarter of the grenades that hit their target did not explode. On the battlefield, it would seem that the PIAT's high rate of fire would be key to engaging the enemy successfully.

One advantage of the PIAT compared to the Bazooka or Panzerschreck was a lack of a gas stream coming from behind the barrel. This made the launcher safer for the crews, made it possible to fire from indoors, and made it easier to hide. However, that concludes the list of advantages. The launcher was very heavy. The PIAT weighed 2.5 times more than the M1A1 bazooka. It also took significant effort to wind it up, about 90 kg. While it was quite possible to wind it up while standing, only the strongest soldiers could do it while prone or sitting down. The 1 meter length of the PIAT was another factor that made it difficult to use for short soldiers. The Bazooka and Panzerschreck had no anthropomorphic limitations, especially not the Panzerfaust, which was effortlessly used by teenagers and old men of the Volkssturm.

The range of the PIAT was also insufficient, only 100 meters. The range of the Bazooka was 275 meters, but the British still considered that insufficient for the open spaces of North Africa. The mountain ranges of Italy, bocages of Normandy, and urban areas of Western Europe were much more suitable for its use. Crews could fight from ambushes, and enemy tanks were restricted in mobility.

Another drawback was the recoil of the PIAT. If the soldier did not press the butt of the launcher against his shoulder tightly enough, then the automatic mechanism would not function, and the spring would not wind up. The PIAT would have to be wound up manually, which would reduce its rate of fire advantage. It's not surprising that the original idea proposed by Blacker and Jeffris was not developed much further and that the PIAT's career was quite short.


SU-12: The Ill-Fated SPG

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Sverdlovsk (modern day Yekaterinburg) was the cradle of Soviet wartime SPG building. The concept of light and heavy assault guns (SPGs) was developed here. However, neither the light nor the heavy SPGs developed here were put into production. One of the reasons for this paradox was the publication of GKO decree #2120 "On the organization of T-34 production at the Uralmash factory and factory #37". According to this document, Sverdlovsk was to produce T-34 tanks instead of the T-70 tank, on which all of their light SPG designs were based. The SU-31 and SU-32 SPGs were left without a production base. All work on SPGs was transferred to factory #38 in Kirov. This was the start of the tragic history of the SU-12, the first SPG to be known under the more famous index SU-76.
On factory #37's design

The factory #38 design bureau could not report of any new serious development by the fall of 1942. This is not surprising, as it did not receive any orders to develop new tanks or SPGs. However, the design group headed by M.N. Schukin had certain projects of their own. For instance, in the fall of 1941, before the evacuation from Kolomna, the factory design bureau developed a cast turret for the T-30 tank, and even produced an experimental batch.

In addition, in May of 1942, designer A.A. Chirkov created a light tank project with Schukin's assistance. The tank, designed in two variants, would be equipped with two M-11 aircraft engines. The design used a T-34 suspension and transmission. The tank was armed with a duo of 45 and 20 mm cannons, as well as a DT machinegun. The first version of the tank, weighing 14 tons, had 10-45 mm of armour. The second had thicker armour, 20-65 mm.

Work did not proceed past a draft project. No blueprints were preserved. At the time, the factory and design bureau's main objective was the production of the T-70 tank, not development of new vehicles. However, work on producing track links from steel alloy #40 instead of Hadfield steel was successful. The joint development of chief metallurgist Nosvkov and NII-48 went into production in December of 1942.

SU-12 cutaway.

The work on light SPGs at the factory #38 design bureau was, in many ways, auxiliary. S.A. Ginzburg was the main ideologue of the SU-31 and SU-32, and he remained the chief designer of the new SPG in Kirov. Schukin's group merely put the designer's ideas into metal. This relationship was taken into account during the investigation in the spring of 1943. Unlike Ginzburg, who was sent to the front lines, Schukin and his group were not punished.

SU-12 from above. The layout of the engine-transmission group is visible.

Work on an SPG did not begin in Kirov right away. A chassis had to be chosen for the new SPG. As trials of the SU-31 showed, the parallel engine layout had an advantage over the SU-32, which was based on T-70 components. Trials performed at the NIBT proving grounds were completed successfully on September 28-29th, 1942. Here it was discovered that the off-road performance of the SU-31 and T-70 was identical. However, the engine of the SU-32 overheated. Ginzburg himself was a proponent of the parallel engine layout. It is not surprising that the SU-31 was eventually chosen as the starting point for a new SPG.

Unfortunately, certain peculiarities were ignored during the chassis selection process. For instance, the fact that the SU-31 was built using the components of the T-60 small tank, while the SU-32 used T-70 components. The SPGs also served a different purpose: the SU-31 was a SPAAG, and the SU-32 was an assault gun. The armour was different as a result.

The complex gearbox used on SU-12 and SU-11 SPGs.

Tactical-technical requirements for the SPGs were formulated on October 16th, 1942. They were largely the same as those for the SU-31 and SU-32. This seems rather odd, given that the parallel engine layout was chosen. In addition, there were requirements for a third vehicle: an SPG on the T-70 chassis. GKO decree #2429 "On the production of experimental prototypes of SPGs" was signed on October 19th. According to it, the prototypes were due by November 20th. Only the Gorkiy Automotive Factory (GAZ) began working on all three variants. The vehicles were indexed GAZ-71, GAZ-72, and GAZ-73.

However, the GAZ assignment was largely a backup plan. The vehicles developed at Kirov were the priority. The SPAAG received the index SU-11 and the assault gun SU-12.

Diagram of the installation of the ZIS-3 in the fighting compartment of the SU-12.

The main project was the SU-12: an assault gun with a ZIS-3 cannon. The installation of an IS-1 (altered ZIS-2) anti-tank gun was also considered, but never put into practice.

Even though the overall concept of the Sverdlovsk SPGs did not change, the design produced by Ginzburg and factory #38 was rather different. The design of the T-70B tank was chosen as the starting point. This modernized T-70 tank entered production in October of 1942. In addition to lengthening the hull and adding a sixth road wheel the chassis used a seventh road wheel as an idler, but without the rubber rim. The hull of the SU-12 was analogous to the SU-31 concept. The cooling system and engine air intakes were designed similarly. A number of components were taken from the T-70B as is, including the driver's hatch. The hatches on the upper front plate used to access the transmission as well as two hatches for engine starters allow us to distinguish this vehicle from the later SU-15M.

Experimental SU-11 SPAAG, December 1942.

The fighting compartment was changed compared to the predecessor. The SU-32 was deemed too cramped, plus the machinegun was clearly superfluous. As a result, the casemate was completely reordered. It became much roomier, and the crew was better protected. Pistol ports covered with shutters replaced a machinegun ball mount. The rear of the casemate changed. It was now equipped with a three-piece hatch. The casemate was also enlarged, as the fighting compartment now had to fit three crewmen instead of two. The vehicle received a 9-R radio. Observation devices along the perimeter improved the visibility.

The same vehicle from the front.

The gun remained the same. It included not just the oscillating part of the ZIS-3 76 mm gun, but also a part of the mount with truncated trails. The trails ate up some of the room in the fighting compartment. The gun mantlet was different than the one on the SU-32: it offered better protection and was simpler to produce.

The gun at maximum elevation.

The SU-11 SPAAG was designed in parallel with the SU-12. The designers didn't reinvent the wheel, but simply took the SU-12 chassis. The development of the AA gun mount was secondary to the design of the chassis. Only the fighting compartment changed: a platform similar to the one used on the SU-31 was installed instead of a casemate. Overall, the design was good. Changes compared to the SU-31 platform were minimal.

Into production with a defect

The plans approved by the GAU required completion of the SU-11 and SU-12 prototypes by November 15th, 1942. A trials program was approved on October 29th. Engineer-Major Getmanov was supervising the assembly of the SPGs at factory #38.

Considering that factory #38 had never worked on SPGs before, this deadline was quite harsh. Even though the Kirov workers approached the task very seriously, the deadlines were not met. However, the SU-11 and SU-12 were finished and began trials by November 21st. Factory mobility trials were completed by the 27th. The SU-11 had travelled 100 km and the SU-12 112 km.

Experimental prototype of the SU-12 at factory trials. Kirov, late November 1942.

It took a while to send the two SPGs to the Gorohovets ANIOP. Both vehicles wee only sent on December 5th. Nevertheless, it was clear which vehicle was the leader in the race for the light SPG program. Stalin signed GKO decree #2559 "On organization of SPG production at the Uralmash factory and factory #38" on December 2nd.

The same vehicle on the Gorohovets ANIOP, December 1942.

This document contained the following:
"The People's Commissar of Tank Production (comrade Zaltsmann) must:
...
b) organize production of the SU-12 SPG based on the T-70 tank with a 76 mm ZIS-3 gun at factory #38 (Kirov), removing the T-70 from production as of January 1st, 1943
2. Ratify the following production quotas for T-34 tanks, T-70 tanks, and SU-35 and SU-12 SPGs:
...
b) factory #38: 
T-70: December 1942: 200
The T-70 is removed from production as of January 1st, 1943.
SU-12:
  • December 1942: 25  
  •  January 1943: 150
  •  February 1943: 200 
  •  March 1943: 200"
The trials were also scheduled to go through. Having two vehicles on one chassis allowed the testers to establish its reliability. As further events showed, the situation with the SU-12 and (partially) SU-11 was far from stellar.

The same vehicle from the right, maximum gun elevation.

Trials began on December 6th with determining the gunnery characteristics. The SU-12 made 64 shots with a rate of fire of 12 RPM. Good stability and satisfactory groupings were observed. Overall, the vehicle was deemed successful. However, the fighting compartment of the competitor SU-71 (GAZ-71) had some advantages. The gun mount was less bulky, the trails did not protrude, and the travel lock was better.

The fighting compartment of the SU-12.

Mobility trials began on December 9th. The SU-71 broke down and did not take part. As for the SU-12, mechanical issues did not bug it in the first days. However, enlarged mudguards had to be installed, since the snow that was being kicked up made it impossible for the driver to see. The same was done to the SU-11, which was going through trials in parallel.

On the 11th, after the march began, an oil leak into the cooling system was found. The issue was corrected, and the march continued. The SPG travelled 300 km during trials, but greater problems were coming. A serious breakdown of the right engine's gearbox occurred on the 400th kilometer. A portion of the mobility trials had to be done on one engine. A similar breakdown happened on the SU-11 after 350 km. The SU-12 failed trials.

The commander's station, showing the 9-R radio. The protruding gun trail can also be seen. It got in the way of the crew's work.

The conclusions made on December 18th said the following:
1. The 76 mm SPG designed by factory #38 is a new type of artillery weapon, capable of supporting infantry and mechanized units with artillery fire during an offensive, solving the type of tasks that are assigned to 76 mm guns.
2. The vehicle presented for trials passed gunnery trials, but did not pass mobility trials, and cannot be recommended for service without the correction of the listed defects. After the defects are corrected, it must be submitted to 500 km reliability trials. The commission deems that if these trials are successful, then the SPG can be accepted into service with the Red Army.
A technical meeting took place at factory #38 on December 15th. Issues regarding the ZIS-3 were discussed, including ideas for how to lighten the system. A 100 kg counterweight was installed to compensate for the mantlet. The travel lock issue was also discussed. The side observation devices were removed, and only the commander retained his periscope. The driver's observation device became immobile. 

The situation with the gearbox was interesting. Ginzburg prepared a memo addressed to the People's Commissar of Tank Production, Zaltsmann, on December 18th. In it, he blamed the poor gearbox gear switch synchronizer on the defects of the SU-12. According to him, poor quality assembly of the SU-11 and SU-12 was the cause of the issues in the trials.

Crew of the SU-12 during firing.

Ginzburg was partially correct. Experimental prototypes built in wartime often had issues with quality of assembly. For instance, poor quality of assembly was what killed the KV-13 in its initial form. However, the KV-13 had plenty of design flaws.

The same was true for the SU-11 and SU-12. The chief designer should have taken note of the similar defects on both prototypes. However, the GKO decree already ordered the vehicles to be put into production. Ginzburg thought that it would be enough to correct the issues later. For now, getting rid of manufacturing errors would be enough. Claiming that similar issues were observed on the T-60 and T-70, the chief designer set off to Kirov to personally oversee the assembly process of the prototypes. This approach was effective. Even though training units reported mechanical defects in January of 1943, none of them had to do with the gearbox. It seems that the defect was defeated. In reality, Ginzburg just signed his death sentence, as his efforts only postponed the widespread breakdowns of the gearbox on his SPGs.

Cover up

While trials of the SU-11 and SU-12 continued, factory #38 was getting ready for production. As soon as the production of the T-70B for December was complete, the SPG took its place. The first 25 SPGs were finished in Kirov by the end of December. Externally, there were no differences from the prototype. The difference was in a lack of side observation devices and a few other improvements. As for the SU-11, its fate was a sad one. The high priority of the SU-12 meant that the SPAAG was forgotten. It was simply omitted from production plans.

The first fighting compartment roof design.

Reliability trials of SU-12 #L212602 were performed on December 29-31st. The SPG drove for 500 km without a gearbox breakdown. It seems that the issue was indeed in the quality of manufacturing, and improvements to the process solved it once and for all.

SU-12 in Teterevino, Kursk oblast, June 1943. This is an early vehicle with no roof.

The most famous change to the SPG, implemented during the production, was the introduction f a roof. At first, the SPG was open from the top, like its predecessors and competitors. Correspondence found in the economics archive (RGAE) indicates that Stalin requested a roof personally. The 6 mm thick roof had three openings for periscopes and an opening for a panoramic sight. The roof was introduced because the crew in the fighting compartment was vulnerable to bullets and shell splinters. The correctness of the roof was proven by the first battles that the SU-12 participated in. The Volkhov Front, where these SPGs were first used, sent a message requesting that roofs be installed.

SU-12, serial number L33432, a testbed for the ZIS-8 system. All vehicles looked like this starting with March of 1943.

Roofs were scheduled to be introduced into production in January of 1943, but due to a lack of 6 mm plate a closed fighting compartment SU-12 was not produced in January or February. According to an order of the Main Artillery Directorate, factory #38 was supposed to produce only SPGs with roofs starting with March 1st. Judging by photos of March production vehicles, this order was carried out. At least 215 SU-12s, over a third of overall production, were built without roofs.

Some authors write that roofs were removed due to ventilation issues, but that is not the case. In addition to a roof, March-June production vehicles can be distinguished from earlier ones by the headlight, which migrated to the front of the casemate. All photos of the SU-12 without a roof show this headlight on the left fender. This is a mark of early production vehicles.

The same with fighting compartment hatches open.

The externally visible parts of the SU-12, which was called SU-76 by that point, were finalized by April. Some internal components were later changed, but that did not affect its look.

One of the solutions to the cramped fighting compartment was the ZIS-8 gun mount. It was designed by the design department of factory #92 under the direction of engineer Abramov. The more compact gun mount got rid of the trails inside the fighting compartment. This improved crew conditions, reduced mass, saved on parts, and allowed the SPG to carry 14 more 76 mm shells. The ZIS-8 system was installed in SU-12 #L33432 in May of 1943. Trials showed good results, and factory #92 recommended that the mount be installed in production.

Cutaway of the SU-12 with a ZIS-8 mount.

However, the star of the SU-12 was beginning to set. Factory #38's design bureau was working on the SU-15 and SU-16 SPGs which had a more compact gun mount without any changes. The ZIS-8 remained as a prototype.

Fatal error

Production of the SU-12 began without much difficulty, but hit a number of issues in January of 1943. Instead of 150 vehicles that were expected, only 40 were delivered. Other quotas that year were also not met: 150 vehicles were delivered in February instead of 200, same in March. In April, factory #38 met the reduced quota of 100 vehicles. The factory was penalized financially due to their failure. However, production of other SPGs experiences similar problems.

Sending the first SU-12s to the Volkhov Front, February 1943.

A common issue with many Soviet wartime production vehicles was the quality of assembly. The first 26 SU-12s were sent to the Moscow SPG Training Center on January 5th, 1943. On January 20th, a memo regarding the quality of the SU-12 and SU-35 (SU-122) was written there. Out of the 26 SU-12s that were received 14 of them were functional, 9 were being repaired, and 3 were sent to factory #40 in Mytishi.

Widespread gearbox failures were not yet observed, but there were plenty of other issues. Repair brigades managed to deal with engine overcooling problems due to an absence of a regulator in the cooling system. A big issue was that the right engine started up first, but the electric generator was attached to the left engine. This led to the batteries being discharged. A number of complaints about the welding on the carriers of internal components were made. Finally, there were issues with the crews not knowing their vehicles, which also led to breakdowns.

SU-12 accepted by crew, spring of 1943. Due to the issues of this vehicle, the crew might not have made it to the front lines.

A technical meeting at factory #38 was held on January 28th, 1943, with Schukin, Ginzburg, and the chief designer at GAZ, A.A. Lipgart, in attendance. Quality of assembly was once again blamed for the gearbox defects, both with the gearbox itself and the vehicle overall. There were already some doubts about that being the root cause of the issue. Another point of proof was that a new gear change mechanism was implemented. The system with two gearboxes that were switched with one lever was unreliable. Nevertheless, Ginzburg still denied that the main source of the issue was the system he designed.

On February 12th, Lipgart sent a letter to the People's Commissariat of Medium Machinebuilding, where he outlined his opinion about the issue. According to him, the issue wasn't with the gearbox. In his mind, the main issue was that the gearboxes were not meant to be used with a parallel engine design. GAZ MM trucks that were being produced at the GAZ factory at that time did not have a single gearbox breakdown like the ones seen on the SU-12.

SU-12 March-June 1943 production.

The first SU-12 went into battle in February of 1943. These vehicles were used by self propelled artillery regiments (SAP) formed according to TO&E #08/191. According to it, the 4th and 5th batteries of the SAP were equipped with SU-12s (4 vehicles per battery) and 3 more batteries were armed with SU-35s (the battery commander's vehicle was also a SU-35).

According to a report by the 1434th SAP, three of its SU-12s suffered from breakdowns of gearbox gears. The overall design of the transmission was also criticized. However, the SU-12 proved itself a valuable combat unit. According to documents, the SU-12s of the 1435th SAP fought better, but this is, perhaps, a matter of comparison with the SG-122, which broke down even more frequently.

The concept of a light assault gun was clearly successful. However, clouds started to gather over the vehicle and Ginzburg by March of 1943.

The same vehicle from the left.

The biggest issues with gearboxes started happening in February-March of 1943, when true mass production of the SU-12 began. Only 35 vehicles left factory #38 in January, but 94 in February and 96 in March. Alarm bells started ringing in late February of 1943. According to a report dated February 25th, 79 vehicles were out of action due to gearbox defects, or 45% of all SU-12s produced by that point. 38 broke during factory trials, 19 in service, and 4 (of the 5 participating) during trials at the Moscow artillery center. This is before a roof added extra mass to the existing 11 tons.

View from the front. Note the headlight that moved up to the casemate.

The situation was catastrophic. However, action was taken in Kirov. An investigation performed by the factory #38 design bureau (without Ginzburg's participation) in March of 1943 allowed the issue to be partially mitigated. Schukin's suggestions consisted of reinforcement of the bottom plate, installation of a flexible clutch, and adding rubber shock absorbers to the engines. Nevertheless, factory management was directly indicating that the parallel engine layout was to blame. The design bureau could not guarantee a complete solution to all problems.

According to Schukin, the only real solution was to radically alter the engine-transmission group, more specifically, use a layout like the one on the T-70. Management agreed, and the development of the SU-38, SU-15, and SU-16 was launched. Changes to production vehicles were made in parallel, which were aimed at solving the issue with gearboxes. In addition to a reinforced bottom plate, rubber shock absorbers, and a flexible clutch instead of a rigid one, other changes were made. The gear changing lever system was replaced with a mechanical linkage. The final drive friction clutches were weakened by 25%.

View from the rear. The roof of the fighting compartment can be seen.

The rate of breakdowns decreased somewhat thanks to changes made by factory #38, but it still remained high. The issues were so common that Stalin personally decreed that the SU-12 be removed from SPG regiments. GKO decree #3184 signed on April 14th, 1943, created special brigades out of factory #38 staff that travelled between units equipped with early production SU-12s and modernized them. Additional friction clutches were introduced as a part of reliability improvements. A number of authors refer to SU-12s modernized in this way as SU-12M, but this index or the index SU-76M was not used in regard to these vehicles.

SU-12 in Staritsa, north of Orel. July 1943.

All of these measures were not enough. Gearboxes continued to break en masse. The GKO ran out of patience. Stalin signed a GKO decree to cancel production of the SU-76 (that is what the SU-12 was called after May) as soon as the hulls produced up to June 1st were used up. Thunder struck on June 7th, when a harsher decree (GKO #3530 "On SU-76 SPGs) was issued.
"SU-76 SPGs suggested by the People's Commissar of Tank Production (comrade Zaltsmann) and GAU KA chief (comrade Yakovlev) and accepted into production by GKO decree signed on December 2nd 1942 have had mass issues of gearbox breakdowns and other defects.
These issues were caused by a reckless approach of the People's Commissar of Tank Production, comrade Zaltsmann, GAU chief comrade Yakovlev, director of factory #38 comrade Yakovlev, and designer comrade Ginzburg to the design of the SPG and its trials.
Measures taken to correct the gearbox defects and other defects suggested by the People's Commissar of Tank Production (comrade Zaltsmann) and GAU KA chief (comrade Yakovlev) carried out by factory #38 according to GOKO decree #3184 issued on April 14th, 1943, did not correct the defects and did not ensure reliable performance of the SPG.
The State Committee of Defense decrees that:
Production of the SU-76 at factory #38 will cease immediately.
...
For the irresponsible proposal of mass production of the SU-76 and improvements made to it, the People's Commissar of Tank Production, comrade Zaltsmann, will receive a reprimand. Comrade Zaltsmann is warned that further omissions regarding the quality of armoured fighting vehicles will result in strict punishment. 
The designer of the SU-76 SPG, comrade Ginzburg, is to be removed from his post at the People's Commissariat of Tank Production, forbidden from further design work, and sent to the NKO to be assigned to the Active Army.
GAU chief Yakovelev is instructed to increase his diligence and control regarding all experimental works on armoured fighting vehicles, paying special attention to correct selection of trials commissions.
The People's Commissariat of Tank Production (comrade Zaltsmann) and GAU KA chief (comrade Yakovlev) are to find and punish the guilty workers of the NKTP and GAU KA that irresponsibly approached the trials of the SU-76 SPG."
Ginzburg was sent to the 32nd Tank Brigade, where he was assigned the post of deputy commander of technical matters. His combat career was not long. He died on August 3rd, 1943, near the Malaya Tomalovka village of Kursk oblast. This incident did not go unnoticed by Zaltsmann either. He was removed from the post of People's Commissar of Tank Production on June 28th. The staff at factory #38 were not punished, as they were not involved in the development of the defective component, which became the Achilles' heel of the SU-12. Schukin's team quickly designed the replacement SU-15M. This vehicle, more commonly known as SU-76M, entered into production in July of 1943. As for the SU-12, only 609 units were produced (608 production and a prototype).

SU-76 battery at starting positions, 2nd Baltic Front, 1944.

Despite the design defects, the SU-76 was not barred from the front lines. As mentioned above, factory #38 managed to partially mitigate the reliability issues. Formation of SAPs according to TO&E #010/456 began in April of 1943. According to this decree, a regiment contained 21 SU-12s. However, due to technical issues, these units saw limited use in the summer of 1943. However, the SU-12 saw plenty of action in units formed according to TO&E #08/191 and other units. The 45th and 193rd regiments fought at the Battle of Kursk, which had a total of 11 SU-12s. 5 more SU-12s were a part of the 1440th SAP. Poor ventilation of the fighting compartment was recorded during the summer battles, earning the vehicle the nickname "gas chamber". 

As the SU-15M began entering service in the fall of 1943, the SU-12 was forced out. Nevertheless, these vehicles were still around in the summer of 1944. They were not recorded separately from the SU-76M (SU-15M) and SU-76I. As a result, it is hard to keep track of Ginzburg's progeny.

No SU-12s survive to this day. However, one SU-11 remained at the NIBT proving grounds at Kubinka, which later turned up at the museum. It is still labelled "ZSU-37" there, even though it differs substantially from the vehicle with that name. Two transmission access hatches and two starter hatches suggest the parallel layout of engines, a layout that was the death of one of the leading Soviet engineer-designers.

OBM-43

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"To the Chairman of the NKV Technical Council, comrade Satel
To the Chairman of the GAU Artillery Committee, Lieutenant-General comrade Hohlov
To the Head of the NKVD 4th Special Department, Commissar of State Security comrade Kravchenko

October 2nd, 1943

NKV special telegram #5014 sent on September 24th of this year tasked NKV OKB-172 and Molotov factory #172, as instructed by the People's Commissar of Armament and GAU Chief, to produce an SPG with a 122 mm gun that fired a 25 kg shell at 1000 m/s.

Treating this task as high priority, OKB-172 completed this task early, and presents it for your review.

The following was established as a result of completion of the draft project.
  1. The objective of creating a 122 mm SPG with a muzzle velocity of 1000 m/s is attainable by means of equipping the KV-14 with a new barrel to replace the model 1937 gun-howitzer and using a one-sided hydro-pneumatic balancing mechanism.
  2. Since the power of SPGs is constantly increasing, you may be interested in the proposal of installation of the OBM-43 gun barrel that fires a 43.5 kg shell at a muzzle velocity of 880 m/s instead of the 122 mm gun with a muzzle velocity of 1000 m/s, as this increases the power of the SPG by 33.5% and improves the effect of the HE and concrete piercing power of the shell.
    This solution not only introduces a more powerful gun, but uses the same ammunition in the SPG and the towed gun, which significantly improves the production and use of these weapons.
Attached is the comparative data of the KV-1 SPG with the OBM-50 project.

Characteristic
Unit
KV-14
OBM-50
122 mm gun
152 mm gun
Caliber
mm
152.4
121.92
152.4
Shell mass
mm
43.5
25.2
43.5
Range at 22 degrees elevation
km
12
21
18
Penetration at 1500 m

At 0 degrees
mm
-
195
195
At 30 degrees
mm
-
160
160
Maximum gun elevation
degrees
22
22
22
Horizontal gun range
degrees
+/- 7
+/- 7
+/- 7
Ammunition capacity
rounds
16
16 (38 with converted fighting compartment)
16
Rate of fire
RPM
1.5
2
1.33
Mass of the SPG with gun and ammunition
tons
47
48
48

Having presented the draft, OKB-172 continues work on the project, which will allow OKB-172 to immediately begin working on blueprints upon receipt of your conclusions.

OKB-172 Chief, Lieutenant-Colonel of State Security, N.A. Ivanov"

Manufacturing Limbo

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"On the T-80 tank: 8 T-80 tanks were built in March and 9 tanks were started, which already have suspensions, engines, and transmissions. Final assembly is stalled due to a lack of armour, elevation, and turning mechanisms. Out of the 17 started vehicles, only 7 have fully turbocharged engines, the other 10 have half-turbocharged engines: with old compression ratios and a cast iron cylinder head. The first 8 vehicles have been broken in, are fully equipped, and are only conditionally accepted while work on the additional return mechanism for AA firing is performed.

It must be said that the factory is dedicating very little attention to the topic of organizing T-80 production due to a lack of production plans.

Senior Military Representative of the GBTU at the Molotov GAZ factory, Engineer-Lieutenant-Colonel Okunev."

"On the T-80 tank: presently, the factory is doing very little work on the topic, with the excuse that there is no production plan for the T-80. In addition, the NKSM and tank directorate do not pay much attention to this vehicle and make nearly no demands regarding production. The factory still has possession of 7 tanks, albeit some of which have half-turbocharged engines, but they sit around idly, while they could be used for training without issues. Acceptance is being delayed because the factory does not wish to correct their defects yet. Aside from production defects, they have issues with splash entering the turret.

Senior Military Representative of the GBTU at the Molotov GAZ factory, Engineer-Lieutenant-Colonel Okunev."

Mosin vs PPSh

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"Jume 16th, 1943
To the Chief of Staff of the 28th Army

1. Totalling up the reports of unit commanders from the division regarding whether or not infantry squads should have rifles or the PPSh, I report that:
  1. The PPSh is the most effective weapon of the infantry squad.
  2. Saturation with the PPSh should be no more than 50%. Leave rifles in the hands of excellent marksmen and snipers (preferably sniper rifles with optical scopes to shoot at a range of over 400 meters). 
Division Commander, Guards Colonel Dobrovolskiy
Chief of Staff, Major Panin"

Theory and Practice

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I covered the precision of the ML-20S gun-howitzer before, but numbers on a table are not quite as fun to look at as the trials themselves. Here are the results from the same gun mounted in a SU-152.


"Results of precision trials, February 2nd 1943
Left group: firing from 1000 meters
Right group: firing from 500 meters."

Via Yuri Pasholok.
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