Semper Fi
A friend of my brother's borrowed one from his dad, back in the 1970's, and I remember him showing us that. Hold down the trigger, and it was bang-bang-bang-bang-bang, as fast as he could rack the slide.
I've always wondered about that. In the dense jungle, wouldn't a shotgun make sense? Maybe one guy per squad carrying one. Seems to me a 5.56 round would deflect if it hit limbs or whatever more than 50 feet out. Whereas a load of buckshot would be effective at the ranges encountered in the bush, i.e. pretty damn close.
Any Nam vets care to weigh in?