The trials of the American Medium Tank M3 in Great Britain gave mixed results. On one hand, the tank had no shortage of design defects. On the other hand, there was nothing else to choose from. The Americans refused to build British tanks under license and Britain's own factories could not meet its army's needs. However, British tanks were far from perfect themselves, and the American tank still had tough armour and a powerful 75 mm gun that outperformed both the British 2-pounder and 3" howitzer. As a result, the American tanks were sent to Africa to prove themselves in battle.
Eye of the hurricane
The North African front stood still after the British retreated to Gazala in February of 1942. This pause allowed to train crews for the new tanks. Small number of Grant tanks began arriving in North Africa back in late 1941, but now shipments really picked up. 666 vehicles of this type were in theater by the end of March.
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| An American instructor demonstrates the new tanks to British tankers. |
Issues with ammunition began immediately. There were warehouses of WWI era 75 mm rounds in Egypt that could be fired from the American gun, with caveats. It was not entirely safe to fire this ammunition from the tank gun, but there was no other choice. The fuses of these rounds permitted ricochet firing, which American-made rounds did not. The British found 90,000 old French fuses and sent them to Egypt to improve American ammunition.
There were also issues with AP rounds. The M72 shot had no cap and shattered when it hit surface hardened German armour. The 75 mm M2 gun could only penetrate the front armour of the Pz.Kpfw.III tank from 500 yards (450 meters), while experimental M61 capped shot could penetrate the same 30 mm of armour at a slope of 20 degrees from a range of over 1000 yards (914 m). This ammunition was not yet available in large quantities. One temporary solution was reusing captured German shells. A German 75 mm shell with a trimmed driving band was compatible with the M2 gun. In trials, it could penetrate the armour of the Pz.Kpfw.III from the same distance as the M61, but it had considerably greater beyond armour effects. A German shell burst after penetrating the tank's armour and would no doubt have killed the crew, while the American shot simply fell into the driver's seat intact.
The 7th Armoured Division hosted its own trials of the Grant's gun. A knocked out Valentine tank served as the target. The tankers opened fire from 1600 yards (1460 m) at an angle of 20 degrees. Two shots hit the side of the tank. Both penetrated. One shot remained intact, a small piece cracked off the second one. Firing at a Pz.Kpfw.III tank from the same range yielded no results. A second attempt from 1300 yards (1188 m) also proved fruitless. Firing at a Pz.Kpfw.IV tank with applique armour from 800 yards (730 m) was also ineffective, but the applique armour deformed and fell off after the second hit.
The Grant's sights were also criticized. Just like the testers back in Great Britain, the North African tankers didn't like the fact that the sight settings were impossible to lock in and they were easily knocked off. The sight also vibrated when the engine was running, which made the gunner's job very difficult. The tank was also not equipped with any indirect fire sights. Crews improvised by cutting markings into the elevation flywheel or installing a clinometer. A procedure was established for indirect fire missions, including firing with the aid of an artillery observer.
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| Grant crews at rest. |
There was another problem with the 75 mm gun. While a vane showed the commander where the 37 mm gun was pointing, it was impossible to tell what he hull gunner could see. The commanders also had to involve the driver in the firing procedure, since the hull gun only aimed within a 28 degree arc. This reduced the mobility of fire. Bad sights also made it impossible to get the guns on target without the aid of a commander's binoculars.
Thanks to the stabilizer, the 37 mm gun could be fired while driving on good terrain at a speed of 12-15 mph (19-24 kph), but in mud the tank waddled side to side. Removable grousers didn't help. They were difficult to install and quickly fell off when driving. The 75 mm gun was much more difficult to use than the 37 mm gun in any conditions, but the tankers still liked it more than the British 3" howitzer.
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| Grant tank on a Diamond tank transporter. The tank's poor reliability meant that this was a common scene. |
The American tanks were poorly suited for driving in the desert in general. The air filters took in too much sand, as a result of which the engines could be disabled after as little as 25 hours of operation. Manufacturing and assembly defects didn't help. Even in ideal conditions, R-975 engines had a lifespan of about 100 hours at this point. The engines also lacked power. Tankers complained that the tanks drive too slowly. There were also complaints about the tracks. They were too narrow and wore out too quickly. The track pads wore down and the tracks themselves stretched out, after which the would fall off the running gear. Sand also got into the fuel system and controls, leading to increased wear. To make matters worse, the tow cables were too weak to pull the disabled tanks.
Sand storm
The new tanks were issued to active units in May of 1942. the 1st and 7th Armoured Divisions were the first to receive Grant tanks. The tanks served alongside Stuarts. For example, the 4th Armoured Brigade of the 7th Armoured Division had 20 Stuarts and 24 Grants in each regiment. The 3rd Royal Tank Regiment was an exception, as it had only 16 Stuarts and 19 Grants.
It was the 3rd RTR that first took these tanks into battle at 07:30 on May 27th, 1942. They took part in a counterattack against Pz.Kpfw.III and IV tanks of the 8th Tank Regiment of the German 15th Tank Division at Bir Hakeim. The fears about ineffective 75 mm shells proved unfounded. The Grants could dispatch the German medium tanks at a range of about 1000 yards (914 meters). However, the Grants turned out to be vulnerable themselves despite their thick armour, and the Germans had a numerical advantage. The 3rd RTR had just 5 Grants and 8 Stuarts left and was forced to retreat. The 8th Hussars from the 7th Armoured fought with about the same success. The regiment reported 30 destroyed enemy tanks, but themselves were left with just two Grants. The 5th RTR had more luck and their losses were relatively small.
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| A destroyed Grant tank in Libya. The turret was blown off by an ammunition explosion. |
A torrent of feedback followed the Grant's debut. It turned out that its reliability hardly improved since the spring. Engine troubles turned into an epidemic. The oil expenditure sharply rose after 400 miles (646 km) of driving, after which the engine quickly became completely useless. Problems were reported with the magneto, starters, air intakes, and electrical wiring.
The volute springs began to break down after 300 miles (482 km) of driving. The British tried many tricks to extend their lifespan, but nothing helped. There were issues with other components, both due to production and design defects. Tankers also complained that the bogeys were easily damaged in battle and the tracks were easy to sever, especially when firing at the front of the tank.
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| A German poses in front of a Grant tank with a destroyed suspension bogey. |
New issues with the guns surfaced. The gun overheated when firing quickly and the semiautomatic mechanism stopped working after 10-15 shots. The breech jammed and cracks were found in some breech blocks. Firing pins also broke often. Armourers had no spares and improvised as best as they could, making replacements out of available materials. The ammunition was also criticized. A portion of 75 mm rounds arriving in North Africa had 23 oz of propelland instead of the required 32 ounces. Defective ammunition had to be reloaded in field workshops.
Complains about sights continued to come in. Crews reported heavy losses among commanders, who had no choice but to stick their head out of the hatch in order to see anything at all. This didn't mean that the tankers preferred the Lee and its commander's cupola. The cupola was cramped and uncomfortable, in addition to making the already large vehicle even taller. Crews didn't trust the observation devices, as they were easily penetrated and broke from the impact of enemy shells against the tank's armour.
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| British crew and their Grant tank. A desert camouflage pattern is applied. |
The armour itself was much better received. The 50 mm gun of the Pz.Kpfw.III tank that easily defeated the Crusader at long ranges was ineffective against the Grant. There were tanks that even withstood 75 or 88 mm shell hits. There were weak spots, however, as the driver's hatch was easy to knock into the tank on a direct hit. Crews tried welding the hatch in place, but drivers complained that driving using the observation device in the hatch alone was unbearable.
There were also complaints about the rivets. The rivet heads popped off when hit with such a speed that there were casualties among the crews. The 37 and 75 mm gun mounts were also easy to jam with bullets or shell splinters. Splash could also pass through cracks, harming the crew. However, these complaints did not outweigh the value of the armour and on the balance it was found to be good.
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| Burning Grant tank. Like Shermans, the Grants burned easily when penetrated. |
The issue with high rates of burning observed on the Sherman also affected the Grant. The odds of a fire or ammunition detonation after penetration were high, as 37 mm rounds were located along the walls of the turret basket and were easily hit by shell splinters. There was no attempt to protect them, as they were too vulnerably placed.
Rain in the desert
Despite the many aforementioned defects, the Grants were considered to be quite combat effective by August. Compared to British vehicles, the Grant's reliability problems were not so serious. Despite the issues with the semiautomatic mechanism and sights, the 75 mm M2 gun was a powerful weapon. Field workshops did what they could with the buggy mechanisms. The love for the 75 mm gun could be seen in a tendency to try and fit as much 75 mm ammunition into the tank as possible, even at the expense of 37 mm rounds. Officially, the tankers were supposed to carry 81 75 mm rounds and 80 37 mm rounds, in addition to 700 .45 ACP rounds for their Thompson SMGs.
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| A commander's Grant tank disguised as a Sherman. |
The reliability gradually improved. Grant tanks with their engines governed to 2100 RPM ran through 900 mile (1448 km) long trials without breakdowns, although oil expenditure was still high. Tankers also adapted the automotive components to their needs. The gearbox synchronizer and hydraulic power steering were disposed of, as they gave more trouble than they were worth.
The Grant remained in service even after the Sherman took the front line role. Removing the weapons and trimming down the crew left a lot of space inside, making it a comfortable command tank. The turret basket was cut off, since otherwise it would be impossible to use the side hatches with the turret locked forward. The commander received a new comfortable seat which could be folded if he needed to stand up and look out of the hatch. Some of these tanks were disguised as Shermans as to not stand out among their younger brothers.
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| An M3 command tank, Musée des Blindés, Saumur. The 37 mm and 75 mm guns are fake and the 75 mm gun mount was replaced with another hatch. |
Many armoured vehicle enthusiasts laugh at the Medium Tank M3. Indeed, the tank had its problems, both visible (high silhouette, inconvenient location of the main gun) and not (poor vision, low lifespan of the engine and suspension). Moving from a handful of hand-assembled prototypes to mass production always causes issues, and the Americans learned about this first hand.
At the same time, it's hard to say that the more experienced British tank builders were faring any better. The Crusader began to crumble into pieces after 500 miles (800 km) of driving and its thin armour could not even hold a hit from a 50 mm gun. The Matilda was better under fire, but its engine and running gear were limited to 400 miles of driving. Both tanks were armed with 2-pounder guns that could not defeat the front armour of the latest German tanks. Even the American 37 mm gun surpassed the British 2-pounder in penetration, while the 75 mm gun was comparable to the 6-pounder. The latter was only installed in a handful of British tanks by the end of 1942, while Grants were already on the front line in large numbers.
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| In the end, the Lee and Grant proved themselves to their crews. |
The Medium Tank M3 appeared on the front lines at just the right time. The British lost Tobruk and Mersa Matruh in the summer of 1942, stopping Rommel at El Alamein. Shermans, Churchills, and other new tanks only arrived in the fall, while the humble M3 shouldered the weight of holding up the North African front.