"To the Chair of the State Committee of Defense, comrade I.V. Stalin
We present the main results of proving grounds trials of 45 mm subcaliber armour piercing shot designed by Military Engineer 1st Class comrade Burmistrov.
The shot with heavy and hard tungsten alloy shows the best results. This shot satisfies the requirement of penetrating at least 60 mm of armour with the resistance coefficient of at least 2400 at an angle of 30 degrees at a range of 300-500 meters. They considerably increase the power of the 45 mm model 1932/37 anti-tank gun.
Shot | Muzzle Velocity | Range | Angle of impact | Thickness | Coeff- Icient | Result |
Exp. 1st variant | 937 | 500 | 35 | 50 | 2580 | All shots gave complete penetration. |
Exp. 2nd variant | 1016 | Complete penetration. Some shot gave deep dents. | ||||
Stock | 760 | Small dents | ||||
Exp. 1st variant | 937 | 300 | 34 | 60 | 2500 | All shots gave complete penetration. |
Exp. 2nd variant | 1016 | Complete penetration. Some shot gave deep dents. | ||||
Stock | 760 | Small dents | ||||
Exp. 1st variant | 937 | 150 | 0 | 90 | 2300 | Complete penetration. |
Exp. 2nd variant | 1016 | Complete penetration. | ||||
Stock | 760 | Small dents |
Experimental and stock 45 mm armour piercing rounds were also tested against a captured German tank.
Shot | Muzzle Velocity | Range | Angle of impact | Thick-ness | Tank part | Result |
Exp. 1st variant | 937 | 500 | 10 | 60 | Lower front | Complete penetration. Brakes broken behind the armour. |
Exp. 2nd variant | 1016 | 500 | 10 | 60 | Lower front | Two complete penetrations, one shot gave a deep dent. |
Stock | 760 | 500 | 10 | 60 | Lower front | Small dents |
10 | 50 | Upper front | Small dents | |||
10 | 30 | Turret side | Complete penetration |
The best results in terms of penetration and beyond armour effect were given by the 1st variant of experimental shot. Drawbacks include lower precision and expenditure of tungsten for making cores. 2nd variant experimental shot has lower penetration but better precision and uses half as much tungsten for cores.
Based on the above results, I consider it most reasonable to accept both variants of 45 mm subcaliber AP shot into service, produce batches of both in April in the volume of at least 25-30,000 units, and begin mass production in May. Subject production shot to trials on proving grounds and on the battlefield in order fully evaluate both types of shot.
We attach a draft State Committee of Defense decree.
Chief of the GAU, Colonel-General of Artillery Yakovlev
Military Commissar of the GAU, Divisional Commissar Novikov
March 28th, 1942"
"Attachment:
45 mm subcaliber shot type 1
- Weight: 900 grams
- Core weight: 500 grams
- Core diameter: 28 mm
- Hull steel: carbon steel type 5, unit weight 7.85
- Core alloy: Reniks-6 tungsten alloy, unit weight 14.6
- Driving band: copper M1-MZ type
- Ballistic cap: iron
- Muzzle velocity: 973 m/s
- Maximum pressure: 2700 kg/cm²
- Gunpowder charge: 6/7 sv 3/38R, 374 grams
- Precision at 500 meters:
- Vertical deviation: 0.41 m
- Horizontal deviation: 0.32 m
- Penetration of armour with coefficient of at least 2400 at 30 degrees:
- 50 mm at 700-800 meters
- 60 mm at 300-450 meters