@DynoDan1 - load some 50grn Vmax’s over 27.3” grn Varget to book length. If it doesn’t shoot MOA or slightly better, you can be certain there’s something broken in the rifle, or the reloading process. I was handed that load over 20yrs ago, and have since fired it in literally hundreds of AR barrels in my own and customer rifles. It may not be the pinnacle of potential precision in every rifle, but it has shot well in every barrel I have ever tested with it which could be made to shoot well at all.
Shooting MOA or sub in an AR is much more difficult than a bolt gun, but getting there really isn’t some insurmountable hurdle - it really just comes down to pushing a good bullet down a good barrel, and using a good enough trigger, build, and support to allow a good enough shooter to avoid screwing it up.
I wish I did better taking photos, but here are a couple relatively CHEAP rifles I built with 1:7” barrels and corresponding targets. Nothing but generic 50grn bullets - Vmax for one and JHP’s for the older rifle. (*note - the group in the second rifle with the red dot sight was fired during function and accuracy testing with a 2.5-16x50mm Bushnell Elite 6500, not the red dot. My astigmatism and red dots don’t play, and I can’t see for crap anymore, so I don’t shoot RDS’s for precision). There’s nothing special here, and I’m no magic marksman. Just free floating, quality barrels, with decent triggers, and decent bullets flying down decent bores. Both of these are 18”, which means I’m about 80-90fps and 9,000 rpm faster than you’d be with a 16” barrel. If memory serves, the first rifle totaled around $600 before optics, and the second rifle around $800. Black Hole Weaponry and Tactical Ordnance barrels, respectively. RRA NM and Larue MBT triggers, also respectively. Again, no magic, no unattainable skill, but some of us have done, and have been doing it for a long time. I built the first rifle pictured in 2015 for a rancher in Utah, and the second rifle in 2019 for a retired Sheriff’s Deputy.
*Group fired with 2.5-16x50mm Bushnell, not with RDS pictured.
This one was built for an engineer out of Minnesota, and is chambered in 6.5 Grendel. It shot about the same 2/3-3/4moa at 100yrds with factory Black ammo, and held onto roughly 1moa pictured here at 875 yards on a 12”x 20” 66% IPSC - although the 78fps ES of the ammo lot meant it sagged a bit more vertically than it should have. Black Hole Weaponry barrel, Geissele G2s-E trigger.
There’s no magic to shooting ~1moa or slightly better with AR’s. It’s just not very easy if you limit yourself with a cheap rack grade chrome lined barrel and a clamshell handguard, firing ball ammo.