IS-2 World War 2 Small-Documentary

The IS Tank was a series of heavy tanks developed as a successor to the KV-series by the Soviet Union during World War II. The heavy tank was designed with thick armor to counter German 88 mm guns and carried a main gun capable of defeating Tiger and Panther tanks. It was mainly a breakthrough tank, firing a heavy high-explosive shell that was useful against entrenchments and bunkers. The IS-2 went into service in April 1944 and was used as a spearhead by the Red Army in the final stage of the Battle of Berlin. The IS acronym is the anglicized initialism of Joseph Stalin (Ио́сиф Ста́лин, Iosif Stalin).
The IS-122 prototype replaced the IS-85 and began mass production as the IS-2. The 85 mm guns could be reserved for the new T-34-85 medium tank and some of the IS-1s built were rearmed before leaving the factory and issued as IS-2s. It was slightly lighter and faster than the heaviest KV model 1942 tank, with thicker front armor and a much-improved turret design. The tank could carry thicker armor than the KV series, while remaining lighter, due to the better layout of the armor envelope. The KV's armor was less well-shaped and featured heavy armor even on the rear, while the IS series concentrated its armor at the front. The IS-2 was slightly lighter than the Panther, much lighter than the Tiger I and Tiger II and had a lower silhouette than both. Western observers tended to criticize Soviet tanks for their lack of finish and crude construction. The Soviets argued that it was warranted, considering the need for wartime expediency and the typically short battlefield life of their tanks.