I went thru Basic and AIT in 1967 with the M-14 as the AR platform was just being adopted. I remember a weapons demo where an M-16 was fired and it jammed 3 or 4 times while it was being fired. Most of the guys were headed for Vietnam and their eyes got buggy when they saw that. I was a Reservist so I went home and we had M-1's. All the early bugs obviously were worked out and they are solid now.
I was 11B10 as my reserve unit art the time was Basic Cadre so we pushed troops for 2 weeks at summer camp. I got a chance to transfer out to a headquarters for a sub-ARCOM and we had 17 units under us. The old man was a bird colonel and I wound up in supply and eventually was supply sgt. I had a Major that cleared the decks for me. He was the S4 and a SGT Maj I reported to. They were both great guys and good to me so my 6 years went by pretty easy. There were a lot of guys in my AIT company that were supposed to go to OCS after the 8 week AIT and they came out with a ruling no college degree no OCS. They all went to RVN as grunts, rather PO'ed ones at that.
I fired M60, M-14A2 (that was a trip), M79 grenade launcher, Ma Duce, & 1911. That was the fun part. Qualified expert on the M60 and barely qualified on the full auto M-14. Those were the only ones fired for record plus the M-14 in Basic.
Most everything down here is USPS eventually. UPS or Fed Ex hands over to the PO. Sometimes stuff comes to Tallahassee then Jacksonville where it sits a week then back to Tallahassee. If we order thru Amazon we usually wind up with a refund and may or may not get the stuff eventually.