What do you do when you have a ton of old tanks kicking around? If you're the Germans, you throw away the turret, and put a bigger gun on top. However, that approach means you still have half of an obsolete tank, with no spare parts for it. The Soviets had different ideas: bury them.
http://tankarchives.blogspot.ca/2013/11/dig-in.html
The fierce nature of the Eastern Front required the Soviet Union to use every tank in its disposal. The majority of the obsolete light tanks were lost in the early days of the war, but various small units were somewhat heterogeneous even later on.
http://tankarchives.blogspot.ca/2013/10/zoo-on-eastern-front.html
The KV-220 and T-150 didn’t meet the Red Army’s expectations, and bets were hedged on the KV-3, 4, or 5 as the Red Army’s heavy tank for the years to come. However, the war began, and dreams of shiny new KVs vanished. As the Germans neared Moscow and Leningrad, everything with a gun and tracks was thrown into battle.
http://ftr.wot-news.com/2013/11/28/historical-accuracy-kv-220/
More information concerning the KV-3, KV-4, KV-5, KV-7, KV-9, KV-220 tanks.
Heavy Tank KV 220
Heavy Tank KV 3
In many publications it is possible to find references to the fact that these vehicles (all or some) were moved to Chelyabinsk, and that the turrets and other parts of the KV-3 tanks were also evacuated there. Unfortunately, this information is not supported by archival documents. For example, in reports of the representatives of the military office at the Kirov Plant, which scrupulously recorded all information regarding the production of KV tanks, it is clearly stated that the T-150, KV-220-1 (as the KV-220 tank was designated in the military office documents) and KV-220-2 (as the incomplete KV-3 tank was designated in the military office documents) were not evacuated anywhere, and the entire time remained at the Kirov Plant. In early October 1941, when the production of KV tanks in Leningrad was practically halted, they decided to turn the experimental tanks over to the troops. All of them underwent necessary repair, during which serial KV-1 turrets were installed on the KV-3 and KV-220 (the KV-3 basically had no turret and the armament on the KV-220 had been disabled at the beginning of the summer).
http://english.battlefield.ru/tanks/14-experimental/62-kv-3-kv-4-kv-5-kv-7-kv-9-kv-220.html
Prototype KVs.
http://tankarchives.blogspot.com/2013/04/prototype-kvs.html