Even when the equipment malfunctioned there usually was, at some point, an operator error.
I've seen one malfunction, it was in the military, pilot said the weapons breaker was popped per SOP, armor said that it was the pilots fault, the TI on the gun afterwards said worn parts, M3 was locked open, belt was broken per SOP at the tray, question if it caught at 3/4 cock and slam fired/ worn sear... but it was the CO's bird.
BUT since everybody observed safe practices, other than a few brown streaks and some hearing loss, everybody walked away.
The usual 'malfunction' was on the heavy weapons range, where both the M2 and Mk. 19 were in use. The Browning requires the action to be charged twice to chamber the first round, the Mk. 19 fires from the open bolt, so on the second cycling the gunner launches one down range.