Army Tanks

The Soviet Union developed the ZiS-2 Model 1941 anti-tank gun in anticipation of an increase in tank armor on the battlefield.  It used a 3inch (76.2mm) cartridge, which was necked down to fire a 2.24inch (57mm) round.   

A BC-271M round, when fired from the Zis-2 Model 1941, had a muzzle velocity of 3250ft/s (990m/s), enabling it to pierce 4.2 inches (105mm) of armor from 1095 yards (1000m) away.

Production of the Model 1941 began in June 1941,

Zis-2 Model 1941 anti-tank gun. Photo by Marko MilosavljevicHowever, production was discontinued by the end of 1941, when the Soviets decided that the tanks that existed at the time did not have strong enough armor and were not powerful enough to justify the Model 1941's use.  

By that time, only 731 Model 1941s had been built.

In 1943, when more advanced German Tiger and Panther tanks appeared on the battlefield, production was resumed. This time, however, the gun was renamed the Zis-2 Model 1943.  Over 13,000 units were produced from 1943 to 1949.