A total of 4,976 SU-100 self-propelled howitzers were produced in the Soviet Union and Czechoslovakia until their retirement by the Soviet Red Army in 1957.
Before 1944, the SU-85 was the main self-propelled anti-tank gun of the Soviet Red Army. It is equipped with an 85 mm L/52 main gun that can fight well with the German Panzer IV tank. However, in the summer of 1943, Nazi Germany began to produce heavy tanks such as Panther (Leopard) and Tiger I (Tiger) in large quantities. Thus, the SU-85 was no longer a worthy opponent against the German heavy tanks. The SU-100 self-propelled anti-tank gun was born, built on the basis of the medium tank T-34-85 in late 1943 – early 1944 and was a version developed from the SU-85 self-propelled gun.
SU-100 self-propelled anti-tank guns began mass production at the Uralmashzavod plant in August 1944 and lasted until early 1948. After that, this model continued to be produced under license in Czechoslovakia in the years 1951-1956. Compared to the earlier SU-85 the SU-100 is both more powerful and better protected over the frontal arc.
The casemate superstructure mounts the 100mm D-10S rifled gun and houses the 4 men crew, for which 33 shells are carried. The downside of the casemate superstructure is the limited traverse of the gun. The engine and drivetrain are located at the rear. This arrangement is very similar to the earlier SU-85, but the internal arrangement in the superstructure has been improved. Compared to the earlier SU-85 the frontal armor was increased from 45mm to 75mm.
For World War 2 standards this is a very powerful cannon. It allowed the SU-100 to engage the Nazi German Panther tank head on at ranges up to 1.5 km. With improved ammunition the D-10S proved to be a potent cannon throughout the early Cold War era. The tracked chassis allows for good off road mobility. The V12 diesel engine provides up to 520 hp. The maximum speed is 50 km/h on roads and about 20 km/h in the field.
The SU-100 first saw action in January 1945 in Hungary, and it was later used in many campaigns of World War II and the Soviet-Japanese war. However, like the IS-3 tank, the combat history of the SU-100 is quite limited because it was born too late when World War II came to an end.
After the war, the SU-100 continued to be modernized and remained in service with the Soviet Army for many more decades. The SU-100s were also delivered to its allies by the Soviet Union and they participated in a number of local armed conflicts, most notably the Arab-Israeli wars.