During World War II, the Soviets developed a massive mobile gun to defend against the German tanks. It was based on the KV-1S tank and was known as ISU 152. On February 14, 1943, it was put into production and designated KV-14. In April 1943, the KV-14 was re-designated as the SU-152. Eventually, the performance of the SU-152 in combat made modernizing the vehicle necessary.
On May 25, 1943, shortly after deploying the ISU 152, they began modernizing the SU-152. This included increasing the armor protection and making other improvements.
In July 1943, development began in July 1943 and the first improved version was ready a month later. This version was designated IS-152. Factory trials occurred in September 1943, this demonstrated a large number of deficiencies and it was sent back for improvements. In October, the second version was ready. This version was the first actual improvement on the original IS-152.
Factory trials of the newer version began immediately followed by state trials on a test range. On November 6, 1943, this version was adopted for production, now known as ISU-152. Production began in December.
Nicholas Moran gives a tour of the most interesting military vehicles. In this video, he looks at the Soviet ISU-152 tank destroyer. What is different about it from the SU-152? What is common between the ISU-152 and some of the German vehicles? How is it that the external fuel tank is not a weakness in the design?
The answers to these questions and more are contained in this episode of “Inside the Chieftain’s Hatch.”
https://www.youtube.com/watch?v=2jT1F3B1qxs