The SU-152, in Russian "СУ-152" (acronym of "Самоходная Установка 152", Samokhodnaya Ustanovka 152, that is "152 mm Self-Propelled Unit") was a heavy self-propelled howitzer used by the Soviet Red Army during the Second World War.
Although its purpose was close support to the infantry, it was quite effective against heavy German armour, like the Tiger tank or the Elefant tank-destroyer. For such reason it earned among the troops the nickname of "зверобой" (zveroboy), "beast hunter".
At the end of 1942 the Soviet Army needed a large caliber artillery piece to engage German defensive fortifications in Stalingrad. At the time it had only 152.4 mm ML-20 towed howitzers or the cumbersome KV-2 heavy tanks, with a main gun of the same caliber. What it needed was a vehicle with the same firepower but with better mobility. They finally chose to mount a 152 mm ML-20S howitzer on a KV-1S heavy tank chassis, replacing the rotating turret —too much troublesome with such a heavy gun— in favor of a casemate configuration. The first SU-152s were completed at the end of January 1943.
Even lacking armour-piercing ammunition, this gun still managed to destroy the heavy German armour even from a long distance, thanks to the kinetic energy and to the explosive power of its shell. Thus, the SU-152 were mass-produced and organized into heavy tank destroyer battalions.
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