Who developed XXX?
RPK
The RPK (Ruchnoy Pulemyot Kalashnikova, Russian: Ручной пулемёт Калашникова or ``Kalashnikov hand-held machine gun'') is a 7.62×39mm light machine gun of Soviet design, developed by Mikhail Kalashnikov in the late 1950s, parallel with the AKM assault rifle.
Mikhail Kalashnikov