Are you serious? I went through boot camp at U.S.M.C M.C.R.D in the very recent year of 1993 and have never heard of such a thing (though I would've gladly accepted one!). The M-16A2 does not have "full auto" because it is a silly waste of ammo... One shot one kill... So the saying goes. We were instructed that the three round burst option was for a charching mega-battaion of Chinese or what have you
