The plant number 8 guns 20K executed serially in 1932.
45-mm cannon mounted on a 20K tank BT-5, BT-7, T-26, T-35, T-70, T-80 and armored cars BA-3, BA-6, BA-10, BA-11, PB-4.
On Rembaza № 6 October 25, 1938 have been tested 45-mm tank gun 20K installed on the tank MC-1. The turret of the tank did not make any configuration except for special performances. box for the mask with a gun. Produced 30 shots. The tests were considered a success. Later, several 10-s MS-1 rearmed 45-millimeter cannon 20K and adopted a fortified. There, the tanks were used as self-propelled or buried in the ground and used as pillboxes. As of 22.03.1941, 68 (according to other sources 75) MS-1 tanks filled with 45-millimeter cannon was on the move.
The plant number 8 in 1941 were given an assignment to create a 2664 45-mm tank guns 20K, and the upcoming phase-out was not planned, because they had to arm a new main infantry support tank (T-126SP or T-50).
In 1942, the creation of guns 20K transferred to the plant number 235, where it lasted until 1943 inclusive.
Volumes of production of 45-mm tank guns in different years were: 1932 — 10, 1933 — 2099, 1934 — 2005, 1935 — 2443, 1936 — 2236, 1937 — 1988, 1938 . — 3604, 1939 — 3949, 1940 — 3230, 1941 — 2759, 1942 — 5090, 1943 — 3040. Total was 32,453 guns.
20K modified a couple of times. So, for example, the standard cannon in 1934 differed from the standard gun 1932 device recoil systems, semi-automatic, hoist, etc., and in the gun standard 1938 introduced electric trigger.
In the 38th, on the part of the tanks BT-7 and T-26 for a 45 — millimeter guns with standard 1938 began installing electric trigger sight "CBT" having a band aiming to stabilize the vertical plane. Stabilization was carried out using a gyroscope suspended in the housing in the head of sight. First World War this system was removed from service due to missing development in the military, operational and structural shortcomings.
It is worth noting that the idea of stabilization tank shells belongs specifically Russia. 02.09.1916, the Commission under the general Manikovsky project could see two-plane gyro stabilizer, a developer who was kammerjunker PP Shilov. The stabilizer was designed for 47-mm single-barrel gun Hotchkiss, which was mounted on an armored car. It was decided to make a prototype of the facility. In 1936, at the Military Academy of Electrical Engineering Workers and Peasants Red Army Christmas project done by an experienced standard Feed mechanism for 45-mm tank guns. The plant number 8 assigned to debug the mechanism and start serial automatic document creation, but the plant during the 2-year delayed the start of a work, and then gave up the job.
In THREADS in 1938 on the basis of 45-millimeter cannon 20K made 45-mm automatic cannon tank "VETOG" having a belt fed by the standard 37-millimeter gun "Maxim". Ordnance Department in the same year decided to finish all the work on the "VETOG", "as the plant number 8 is engaged in 45 — and 37-mm automatic cannon. Cannon that will be worked out before, will give for the use of the tanks. "
Fascinating and the work on the 45-mm armor-piercing shells for chemical 19K and 20K. Given shell, tearing the armor, generate poisonous gas that destroyed the armored vehicle crew. In 1934, Scientific Testing artillery range began testing 45-mm armor-piercing projectile chemical "blueprint 180."
22/02/1938, the Ordnance Department had approved the design TTT 45-mm tank gun has improved ballistics for the new towers tanks BT-7 and T-26. Piercing shell modern guns (mass 1420) was due to punching 40-mm armor at a distance of 1 km at an angle of meetings of 30 °. The initial velocity of the projectile to be equated with 860 meters per second. Sleeve chuck old, in other words, the original speed was assumed to increment by increasing the length of the barrel or the weight of the charge. The vertical guidance from -5 ° to +3
0 °. Weight of the gun was about 400 kg. Implementation of the intended target was completely real, and by 1941 there were new experienced 45-mm cannon with advanced ballistics: Anti 7-1 (plant number 7, the initial velocity of the projectile — 885 m / s), ship's 80-K (plant number 8, the initial velocity of the projectile — 960 m / s). In the design office Shpitalniy began developing a 45-millimeter automatic tank gun with an improved ballistics. But these works were soon gone. Also, the tests were carried out 37-mm automatic gun Shpitalniy installed in the tower T-26. Initially designed as an anti-aircraft gun, but the corners of the vertical guidance to the T-26 ranged from -7 ° to +12 °. 37-mm gun OKB-2 in the series did not go.
In 1942 he made a 45-millimeter PTP standard 1942 (M-42), which differed from the 19K increased length of the barrel to 68.6 calibers. In the OKB-172 on the basis of M-42 in the 42-43's. standards have made seasoned 45-mm tank gun BT-42 and BT-43 with a barrel length 68.6 calibers. Guns BT-42 was created for the T-70 and BT-43 — T-80. These guns were not taken into service.
According to the article by Alexander Shirokorad, the magazine "Arms and equipment"