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Q: Was the S-54 ever used on the T-34? Could it be mounted in the T-34 model 1942 turret?
A: Yes and yes. The model 1931 76.2 mm AA gun (ZK) from which the S-54 borrows its ballistics was recommended for installation in a tank since 1940, but the performance of the F-34 put those plans on the backburner. When the threat of the Tigers, Panthers, and Ferdinands loomed in 1943, many pre-war improved ballistics projects resurfaced, including the AA gun. As the T-34-85 was already in development, the S-54 was seen as a temporary measure. After trials, it was recommended as an upgrade to all T-34s currently in the field, but shortages of ammunition cut those plans short. In any case, the trials ended on October 19th, and the T-34-85 would be available only a few months later.
The gun was installed in the mass produced T-34 model 1942 turret, with some changes. Due to the longer shell, the position of the loader had to be altered. The tank could also carry less ammunition: 52 shells in the hull, 7 in the turret bay, and 9 on the sides of the turret (5 on one side and 4 on the other).


