Kalashnikov's new thing was also the caliber, 7.62x39. They called it an intermediate round, meant for 1 or 2 hundred yards at most (accurately). The SKS uses the same round. .
Wrong....the cartridge was also copied from the stg44....8mm Kurz basically the standard 8mm rifle cartridge cut in half.
Soviets as usual saw this and went....wow what a good idea....lets take that and say we came up with it at the same time.