During the Korean war there were many different infantry weapons to choose from. It was mix and match. If a guy in my Dad’s platoon got wounded or worse his weapon(s) was fair game. What he told me was some of the guys liked the captured Russian burp gun so much they started to carry it. It was a really good weapon. Then they realized the sound of it could potentially draw friendly fire so that didn’t last long.
My uncle who carried the M1 Carbine said his unit was walking through an area where the norks had been wiped out and there were all kinds of Russian guns laying around and he picked up a burp gun and some ammo he carried with his M1 for a while. On a particularly long hot day he decided why am I carrying this heavy POS and tossed the burp gun into a rice paddy.