The ISU-152 assault gun was used the same as the earlier SU-152—a large gun mounted in the hull of a heavy tank. The ISU-152 used the same gun as the earlier SU-152 but was built on the hull of an IS-2 tank instead of the older KV-1. Over 3,200 vehicles produced in total between 1943 and 1947, with 1,885 ISU-152s built before the war’s end. The main gun used a powerful OF-540 high-explosive shell containing nearly 6 kg of TNT which helped it perform it duties of breakthrough and bunker-busting. The troops greatly appreciated the heavy assault guns, describing them as "Nekrasivo, no spasibo!" ("Not pretty, but thanks!") The ISU-122 was identical to the ISU-152 with the exception of the main gun, The ISU-122 used the more powerful 122mm D-25S gun that was more effective anti-tank gun, but also filled the role as an infantry assault gun. The pack includes one hull for an ISU-122 or ISU-152 assault gun. It also includes both barrels for the 122mm and 152mm assault gun.
In Flames Of War
The Guards Heavy Assault guns are prefect for clearing enemy troops out of trenches and gun pits and devastate bunkers. They can also apply their massive weaponry against enemy tanks. Both ISU heavy assault guns boast 9 frontal armour with 7 side armour and 2 on top. They are slow tanks. The ISU-152’s gun has anti-tank of 13, and a massive firepower of 1+, making sure that whatever it knocks down, stays down! The ISU-122 has anit-tank of 15, firepower 2+, making it an effective tank-killer, capable of destroying any enemy tank.