ACS IT-1 – the world's first artillery tank

Even during World War I, there was a problem of lack of mobility regimental cannon caliber 76 mm, which forces a few people managed to move quite slowly and for short distances. Attempts have been made to carry a gun in the back of a truck, but it did not solve the main problem. In Soviet Russia, working to find ways to increase the mobility of the heavy guns continued. AT 1927 g. advanced caliber gun design was developed 76 mm, which was lighter than previous models. However, Soviet engineers went further - they decided to mount a 76-mm gun on the chassis of the T-26 tank.

So, at 1932 g. there was the first self-propelled artillery SU-1, where the gun with two machine guns placed in a closed armored cabin. However, the novelty of the idea at first was not appreciated - primarily because, that embarrassing lack of towers.
AT 1933 g. We attempted to accommodate a 76mm gun turret in the modified T-26. However, it turned, this tower, despite the apparent capacity, in fact, in very close, so nowhere to place sufficient ammunition, so the issue of the artillery of the T-26A was terminated.
Instead they began to produce an improved version of the SU-1 - artillery tank AT-1. AT-1 had a PS-caliber gun 3 76 mm and two machine guns DT. The conning tower could accommodate 46 shells. AT-1 was the world's first self-propelled infantry gun - a very powerful weapon for that period of time. For comparison it should be noted, that in Germany at the time the infantry accompanying tanks were not, later a similar fighting vehicles developed by German engineers based on the Soviet experience.
In the USSR, it was released only 10 self-propelled guns AT-1. To replace them soon came another artillery unit - SU-5.

Specifications prefer-SAU AT-1

Foto SAU AT-1

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