"Characteristics of armour penetration of cannons and effectiveness of mines on enemy tanks
Based on experience of combat and trials
- Trials against an 88 mm SPG "Ferdinand" show the following results:
- Armour of the SPG: roof: 45 mm, rear: 80 mm, side: 80 mm, front: 200 mm, gun mantlet: 110 mm, front hull: 200 mm.
- Effectiveness of firing:
- Anti-tank rifles: firing at the side armour from 80-100 meters with the BS-41 bullet penetrates 50 mm of armour forming a 20-22 mm deep indentation. Firing at the tracks can break track pins and the track links. The rifle can penetrate observation periscopes and jam the gun ball mount.
- 45 mm gun mod. 1937: from 300 meters the shell can penetrate the first armour plate and break up against the opposite side, splitting into small pieces and damaging the gun mechanisms and its crew, destroying the engines. From 150 meters, three subcaliber shells made complete penetrations 22 mm in diameter. From 150 meters, the armour piercing shell makes a 22-30 mm deep and 50-60 mm wide indentation. Firing at the front armour from 100 meters, the subcaliber shell makes a 50-60 mm deep indentation. The core remains in the armour. The armour piercing shell makes a 25-30 mm indentation in the front armour.
- 76 mm mod. 1942 ZIS-3. The subcaliber shell makes a penetration 27 mm in diameter from 400 meters. The depth of the indentation is 100 mm. The destructive power is the same as of the 45 mm subcaliber shell. The armour piercing shell makes a 22-30 mm deep dent 400 mm in width. Firing at the front armour from 200 meters with a subcaliber shell makes a dent 100 mm deep and 110 mm wide, the core remains in the armour. The armour piercing shell makes a 35-37 mm deep, 110 mm wide dent. Firing at the tracks destroys the track pins and destroys the tracks. Firing at the gun mount jams it.
- 76 mm mod. 1927. The HEAT shell penetrates the side armour to a depth of 45-50 mm.
- 85 mm mod. 1939 AA gun. The armour piercing round can penetrate the side from 800-1200 meters. The breach is 110 mm wide from the outside, 200 mm from the inside. After penetrating the armour, the shell makes a 57 mm deep indentation in the other side, after which it bursts, showering the crew with its own splinters and armour fragments, destroying components.
Firing at the front armour from 200 meters results in a 100 mm deep dent, with spalling and destruction of the rivets holding on the applique armour, as well as destroying the controls and radio equipment. If a shell hits the track, it is destroyed within a radius of 0.75 meters.
- 122 mm mod. 1931/37 gun. Firing an HE shell from 400-800 meters at the side armour with the fuse set to delayed action gives the following results: deep cracks are formed along the welding seams spanning the entire length of the casemate, the bolts of all the plates connecting the casemate at the bottom were torn off.
- 122 mm mod. 1938 howitzer: firing HE shells from 400 meters is ineffective.
- Effectiveness of anti-tank mines: in the prior defensive fighting, our units used chiefly YaM-5 mines, which are not entirely effective against PzVI tanks and Ferdinand SPGs. Practice shows that they are effective in destroying PzIII and PzIV tanks. Several areas had HE mines (50 kg charge connected to a 250 kg bomb) installed. The effectiveness of these mines is high. If a PzVI tank or a Ferdinand hits this mine, it is reduced to a heap of metal.
- Effectiveness of incendiary bottles: the most vulnerable area of the Ferdinand to bottles with incendiary fluid is the top armour where vents are located. It is easiest to disable the Ferdinand with bottles of incendiary fluid tossed onto the vents on top of the front part of the hull. It is also possible to throw a bottle into the hull through one of the hatches. The most convenient hatch for this is positioned in the rear of the casemate. This hatch is used to throw out spent casings during combat, so it is frequently open.
Chief of Staff of the Armoured and Motorized Forces of the Central Front, Colonel Korotkov
September 24th, 1943."