"People's Commissar of Defense
December 10th, 1940
To:
Central Committee of the VKP(b), comrade Stalin
Council of People's Commissars, comrade Molotov
Committee of Defense of the Council of People's Commissars, Marshal of the USSR comrade Voroshilov
In accordance with the minutes of the meeting held by Marshal of the USSR comrade Kulik on the issue of tank and anti-tank armament, factory #92 was tasked with development and production of an experimental 55-60 mm anti-tank gun with the following characteristics:
- Muzzle velocity: at least 1000 m/s
- Penetration: 70 mm from 1000 meters at 30 degrees
- Mass: no more than 950 kg
- Horizontal traverse range: 60 degrees
The 57 mm caliber was selected to solve this problem.
The gun is not yet ready. Factory #92 is completing development of blueprints and only several components are in production. Only the barrel has been produced and tested using a pillbox gun mount.
During the trials a muzzle velocity of 1000 m/s was recorded.
As the propellant was picked by factory #92 from expedient gunpowders, the combination of which could not be satisfactory, the final ballistic data to design complete ammunition was not obtained.
Because of this, a barrel of the 57 mm gun was installed on the mount of a 76 mm model 1939 divisional gun and sent to Leningrad to develop the projectile, test ballistic qualities, and approve them so that ammunition can be developed.
It is not impossible that the maximum pressure calculated at factory #92 (2890 kg/cm²) will not be enough to obtain a muzzle velocity of 1000 m/s, which will require design changes to the barrel and development of a special primer.
Factory #92 has now turned its primary attention to using the 57 mm barrel of the pillbox gun as a tank gun.
This direction cannot be considered correct, as the use of the 57 mm gun caliber in pillboxes and tanks can only be allowed if it is present in field artillery. Factory #92 should develop an anti-tank gun first.
Based on the above, on this December 10th I present a draft decree to the Committee of Defense that defines the production of experimental prototypes of the 57 mm anti-tank gun, ammunition for it, and complete trials.
Marshal of the Soviet Union, S. Timoshenko"
