S-53 Turret

"Protocol
of investigation of several issues of equipping the T-34 tank with a stock or expanded turret ring with an 85 mm S-53 gun
January 14th, 1944
Gorkiy

Decisions:

When developing working blueprints of turrets for tanks with stock or expanded turret rings, take into account the following:

1. The main aiming device is the refracting scope. Also install the 10-T-15 telescopic sight.
2. Instead of a periscope, the gunner should use a MK-4 sight.
3. The angle of gun elevation should be no less than 22 degrees and the angle of gun depression should be no more than -5 degrees.
4. The turret should fit 35 machinegun disks in the turret bustle. The turret with the stock turret ring should replace these disks with shells.
5. The gunner's seat should be adjustable height-wise. In the turret with an expanded turret ring, make the commander's chair removable instead of having it flip back.
6. Put the radio in the turret in the tank with the enlarged turret ring."

CAMD RF 38-11355-2224

The "T-34 with stock turret ring" is most commonly known as T-34-76. Photographs of this old tank with the new gun can be seen here.