Not done well I grant you!
Not done at all. Kalashnikov worked in competition with Simonov to develop a Soviet rifle. Simonov won out, with the SKS-45, a scaled down version of a Soviet anti-tank rifle(PTRS-41), partly of Simonov’s design. It had a tilting bolt, as does the StG-44. The AK has a rotary bolt. The Soviets couldn’t figure out the art of forming sheet metal, so had to mill down a block of steel for the receiver. The sloppy tolerances of the AK proved to be its’ saving grace.