Soviets were developing light self-propelled artillery in 30' years, but SU-8 was classified as heavy artillery. Being build on T-28 chassis, SU-8 kept most from this tank, only the mechanical parts were changed. Still, with the decrease of production of T-28, development of SU-8 was stopped.
SU-8 was prototype medium (or heavy) mobile artillery of Soviet Union, developed from 1932. By some sources it's arment had to be 76mm howitzer, but other sources (WarGaming) specified the armament to 122mm or 152mm howitzers (same as in SU-152). In World of Tanks, SU-8 is powerful mid artillery.
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