Key point: Both America and Russia worked to build tactical nuclear-bomb cannons to use on the battlefield.
In the 1950s, both NATO and Warsaw Pact doctrine focused on the employment of tactical nuclear weapons. Truly strategic nuclear weapons and the doctrine of mutually assured destruction (MAD) were at their infancy at the time, so nuclear weapons were seen as a tactical as well as a strategic tool.
As a result, both the United States and the Soviet Union developed a multitude of battlefield nukes, from the tiny Davy Crockett nuclear recoilless rifle to the M65 Atomic Cannon. The Soviet Union responded in kind, beginning the development of their own massive atomic howitzers and even mortars.
The largest of these pieces was the massive 406mm Soviet 2A3 “Kondensator.” But in the end, this piece was a failure. It was mechanically complex and obsolete by the time it was adopted.
Why did the Soviet Union produce these massive white elephants? Can anything be learned from the folly of the 2A3? Why was the caliber so huge compared to American guns?
The story of the 2A3 begins in 1954. The United States had rolled out the 280mm M65 atomic cannon just a year before, and the Soviets needed to catch up. Their response came in two forms, the 406mm howitzer (2A3/Object 271) and a 420mm mortar (2B1/Object 273).
The initiative to develop these two weapons was approved by the Council of Ministers in April 1955. The first ballistic test barrel was completed later that year, and in December 1956 the first prototype was created by mating the gun with the chassis. The design was paraded on Red Square in 1957.
The chassis for the 2A3 was derived from the T-10 heavy tank with additional hydraulic shock absorbers to absorb the massive recoil force of the 406mm projectile. Despite these measures, the 2A3 would travel a few meters back with every shot, and inevitably something would break and minor repairs would have to be conducted.