Object 705: A Tank that was even bigger than the IS-7 we know so far.
For quite a while Wargaming began searching for new hidden and forgotten tanks that could potentially be the final vehicle to play on their game. A lot of people already know the biggest prototype the USSR made: The IS-7 (Object 260) that was more than ready to hit production, but general logistics made the project come to a full halt. But hidden in the files there was a variation of the IS-7 itself that carried even a bigger gun than the already powerful 130mm S-70. However it fell on the same fate as the IS-7 and even worse, as the IS-7 DID manage to get a prototype out of it.
Background
While NII-100 (Soviet technology research institute No.100) was working on its project (Object 260, the IS-7), in Chelyabinsk a new generation heavy tank was developed – the Object 705. The vehicle was supposed to have roughly the same characteristics as Object 260, but the tank design (arrangement) was different. On paper (in the project) the tank was supposed to have the 122mm BL-13 gun, but unlike Object 260, it was supposed to have the turret in the rear. This vehicle (Object 705) requires more serious research, but it’s possible to see how the vehicle would look like.
However, both the Object 705 and Object 260 were not the apex of the evolution. Apart from the Object 705 65 ton variant, Chelyabinsk design bureau worked on a 100 ton variant, designated Object 705A. It was different from the 65 ton variant in two things: armor and gun. And when it comes to the gun, we know what it would be: the 152mm experimental gun M51. Considering the Object 705 had (with 65 tons) roughly the same armor as Object 260, you can imagine what kind of monster would Object 705A be.
In case you are wondering, what the hell is the M51 152mm gun: an experimental Soviet gun. Barrel length was L/50. The project was ready and considered in June 1947, modifications were requested and the modified project was ready in December 1947. The gun ballistics corresponded to the 152mm BR-2 gun and the project was made so a lot of parts would be unified with 152mm M-31 gun, designed for heavy SPG’s. In order to reduce the recoil, a massive muzzle brake (that absorbed 70 percent of recoil energy) was installed. At the point of its inception, the gun was the most powerful anti-tank gun in the world. However, no platform was ever created to put it on, repeating the history of 107mm ZIS-6.
In World of Tanks
Two years later the vehicle is starting to get through some internal testing in order to not be overpowered. Given the massive size of it's gun, it might take some time until there's a good balance without overshadowing the Type 5 Japanese Superheavy, which is another similar tank that carries a masive gun on it's own too.
Given how the vehicle never got out of blueprints, we can at least have some pictures of it to have a better 3D picture out of technical drawings:
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