OverviewThe ZiS-19 is a tank gun developed in 1941 for the T-60.
The ZiS-19 was developed by Zavod 92 of ZiS with development starting in August 1941. The ZiS-19 had the same ballistics and ammo of the 61-K anti-aircraft gun. The ZiS-19 was promoted by the design bureau, so it was to be tested along with the 45mm 20-K. The ZiS-19 was considered the more promising proposal, the 45mm 20-K was much heavier than both the ZiS-19 and the TNSh already mounted in the T-60. The 20-K made the turret unbalanced and created difficulty when attempting to turn the turret with the gun at high elevations. A 30kg counterweight was proposed to be mounted, but that would have made the already cramped turret even more cramped.
Zavod 92 was tasked with the production the the ZiS-19 prototype by January 15th, 1942, with a completed tank expected for trials to be ready on February 1st. Zavod 92 completed working blueprints from December 20, 1941 through January 19th, 1942. The prototype was constructed from January 12th - 19th. The ZiS-19 was mounted in the turret on January 19th, and a completed turret arrived on January 27. The blueprints of the ZiS-19, including a list of parts and its characteristics were sent to GAZ on January 14th.
The ZiS-19 was installed with minimal changes to the tank. Only a few changes were needed, none of which were difficult. The seat was shifted to the left, the gun was installed in a modified gun mount, and a new gun mantlet was created. The gun took up less space compared to the 20-K and the TNSh.
The deadlines were missed, gunnery trials went from February 21 - 24, 1942. 181 shots were fired from various elevation angles. The gun was considered satisfactory in most aspects. Complaints included the small size of the turret and the uncomfortable seat.
On the 27th of February, 1942, Artkom instructed that the T-60 with the 45mm 20-K and the T-60 with the 37mm ZiS-19 should be sent to the Gorohovets proving grounds by March 9th. However this didn't pan out, instead modifications to the T-60 with the ZiS-19 were made. Major reconstruction of the turret was made, the match was moved from the roof to the rear, and an observation device from the T-70 was place there instead. The turret shape was changed, the mantlet was now cast. The gunsight was moved to the left, and the DT coaxial machine gun was put in its place. The tank arrived at Gorohovets proving grounds on March 27th. The GAZ T-60 armed with the 45mm 20-K didn't arrive either, instead the T-70 tank arrived on the 18th of April.
Trials of the T-60 armed with the ZiS-19 in the new turret began on April 19. The gun proved to be equivalent to the 45mm 20-K in penetration, precision and rate of fire, but the higher velocity of the 37mm gun reduced the lifespan of the ZiS-19, and the HE shell was inferior. This meant that the ZiS-19 would not be as effective versus infantry, and that was an issue as it was one of the intended roles. The ZiS-19 was commended for it's performance none-the-less, and if the defects could be resolved it could have been used on the T-70. However it was too late, by July 19th the T-60 was out of date, and the T-60 ceased production. The ZiS-19 could have been considered for use in the T-70, but the new 45mm VT-42 was considered more promising.