hmmm, i believe, that it is quite simple, in a script, or w/e, you simply put:
aP action["STR_ACTION_TAKEWEAPON","M16"]
and he will take an M16 - however I may have the syntax wrong slightly so also try:
aP action["M16","STR_ACTION_TAKEWEAPON"]
and there you have it. Simple, fast, fun, and effective