You want a 1:8 barrel and 69-77 gr sierra match king bullets.
The most important aspect being velocity deviation. You need those bullets going the same speed. This is done by separating brass an bullets by weight, neck run-out, neck/bullet tension and accurate consistent powder measures.
I've pulled 3/8" 3 shot groups at 100 yards out of a 16" stainless bull barreled AR15 with of all things, Wolf 62gr fmj. This was during a precision rifle class. Must've been a great batch from new dies.
I've also run 2"@100 yards with the same ammo/gun.
I prefer the M262 mod 1 77grain SMK from BHA for the SF guys. Sweet shooting, and I don't have to load it.
I could make a list of a bunch of guns i have, or "have", or wish I had. Why would one feel compelled to provide that infornation freely? Do you feel the need to show off? Is it some immature game of oneupsmanship?
Why do you feel it necessary to list your guns?