I was in Nam in 1969/70. In those days the RF/PF troops were armed with the M-1, BARS, Grease guns, Thompson submachineguns and so on. RF/PF = Regional Forces/Popular Forces troops which loosely equated to our National Guard/militia forces. These "second-line guys" got armed with the older stuff while the active duty South Vietnamese got the more modern stuff like our M-16 rifles. Other troops, like the mercenaries, got armed with captured or foreign firearms. It was not unusual to see a guy from Cambodia working for our side armed with a captured Chi-com or Russian AK-47 type rifle. Sometimes old French firearms were issued to certain groups of people like Mountengard fighters. Some of these French firearms had been used by the French Army, captured by the communists and then re-captured by the South Vietnamese or Americans to be re-issued to people on our side. There were also supplies of foreign made firearms, like some SMLE rifles from India being used in Viet Nam. Heck, in some of the really backwards places, very old cap and ball rifles were actually used by some people. You name it, and it was probably used over there by somebody somewhere. And then there was the special ops teams with all their firearms too....