As for the M-14, it was miles more effective round for round than M-16s or AKs - and supremely accurate. I always hit who I was aiming at and when I was a competitive shooter used a match M-14 to score 34 consecutive V-ring bullseyes at 600m in 1978. M-14s held the 1,000m iron sight record and may still have it, as far as I know. So much for the "simple physics".
I still haven't heard anything from you about your combat experience. What the heck do you know about ammunition loadouts, resupply options, or what works best? All I know for sure is that you never, ever run out of ammunition. If you're really lucky you only do that once and then never again.
I didn't say that a combat veteran would design a better weapon. What I did say was the combat veteran - or veterans - should be the Program Manager over the talented designers to guide their efforts towards a system that is precise, reliable, element-proof and the best possible caliber to ensure long-distance lethality/obstacle penetration. A combat veteran would better than anyone else the characteristics and therefore the specifications the design team would strive for.
Better weapons. Almost anything is better than the gas tube M-16. How about the HK G36 or the SIG 550 or the Galil/Valmet for starters?
Bottom line - our weapons must be the finest possible in all respects, price be hanged. Our kid's lives depend on them so we need the best. Not just what some comfortable DoD civilian thinks we should have.
But we need drones and GPS guided Ipads...