Usage:

Production tanks: none.
Experimental tanks: T-60.

Whilst conducting research related to increasing the T-60 Light Tank's armament power in February 1942, the staff of the experimental department of Factory #2 of the People's Commissariat of Armament, installed a 23mm gun into the T-60 turret. The 23mm gun was a modification of the Aircraft Gun VYa. The tank version turned out to be somewhat more effective than the aviation one, but the operational experience was short lived, because in 1942 there was not enough 23mm ammunition even for the IL-2 Ground Assault Aircraft. Lastly, the abrupt gun recoil jammed the tank's turret. Altogether sixteen VYa guns were manufactured for the T-60 tank in March-April, it is unknown though if they were installed on any tanks.

Translation: Rodion Podorozhny
Proof-read: Chris Amundson
Sources: "Artillerijskoye Vooruzhevie Sovetskikh Tankov 1940-1945" Armada-Vertical, #4, 1999

Usage:

Production tanks: none.
Experimental tanks: T-40.

Even though the tank guns of 45mm calibre and smaller were considered obsolescent, the experimental work on them continued. This happened because RKKA accepted the T-40 Light Amphibious Tank into service, which had an armament consisting of a 12.7mm machine-gun DK (and later - DShK) already considered insufficient in 1940.

As far back as in 1939, OKB #16 headed by Ya.G. Taubin was ordered to develop a clip-loading 23mm automatic gun for the T-40 tank. The prototype gun received the designation PT-23TB (23mm Tank Gun of Taubin and Baburin design), and was built "in metal" by OKB #16 on the basis of the design of the light 23mm infantry anti-tank/anti-aircraft gun. An experimental tank, whose turret contained the only experimental prototype of the gun, was made operational, and used for firing range trials in December 1940.

Nevertheless, in implementing the instruction of the People's Commissariat of Armament, on 25th January, 1941, the gun was removed from the tank and sent to Factory #5 where work on the armament for armoured snowmobiles for NKVD was underway. Soon, the Head of the Design Bureau Taubin was relieved of duty and arrested, and all the advanced work on the PT-23TB gun was stopped.

Muzzle velocity of the armor-piercing projectile is 830 m/s.

Translation: Rodion Podorozhny
Proof-read: Chris Amundson
Sources: "Artillerijskoye Vooruzhevie Sovetskikh Tankov 1940-1945" Armada-Vertical, #4, 1999

Usage:

Production tanks: "Renault Russian", T-18 (MS-1) mod.1927-1930, T-26 mod.1931-1933
Production armoured cars: BA-I, BA-27, BA-27M
Experimental tanks: T-19, T-20

The French 37mm Hochkiss Tank Gun was a redesigned variant of the naval gun accepted into service back in the 1880s. The gun had an automated breech-block (this means the breech-block had to be opened manually). The gun's compressor was hydraulic, its recuperator was spring-based. Its ballistics were already considered mediocre by the beginning of the 20th Century; in the 1920s its ballistics were significantly inferior to that of other guns of the same class. The performance of the round was ineffective against both armoured and soft targets.

In 1928, Peter Syachentov improved the gun, among other things the striker and trigger mechanism was improved; the gun's mantlet also underwent some changes. Nevertheless, the gun's performance remained mediocre at best. The gun was officially accepted into service in the USSR in 1920. The original Hochkiss Gun was manufactured at Factory #8 located in the town of Podlipki near Moscow. At that factory it received the designation of "7K", some documents of that period named this gun PS-1. In June 1928, the procurement order for the first 206 Hochkiss guns was given out.

In total, the factory produced 1080 Hochkiss guns during 1931-1932. The manufacturing of this gun was cancelled in 1932. The 37mm Hochkiss Gun was installed on the tanks "Renault" and "Renault Russkiy" manufactured by Sormovo Factory #112, MS-1 (T-18), twin-turret T-26 tanks, they were also installed on the armoured cars BA-27, BA-27M, and BA-I. By November 1, 1936, Red Army possessed 1327 combat and 60 training 37mm Hotchkis guns.

*Hochkiss data in numerator; PS-1 data in denominator.

Translation: Rodion Podorozhny
Proof-read: Chris Amundson
Sources: "Artillerijskoye Vooruzhevie Sovetskikh Tankov 1940-1945" Armada-Vertical, #4, 1999
T.Jentz "Panzertruppen" vol.1, 1996
A.Shirokorad "Entsiklopediya Otechestvennoi Artillerii", 2000
M.Svirin, A.Beskurnikov "Pervie Sovetskie Tanki", Armada #1