I have an AR I assembled in 6.5 Grendel that is consistent 3/4" all day with factory ammo. It has produced more than a few sub 1/2 MOA groups with me shooting it off a bipod and rear bag. I have never hand loaded but I assume it could get better with a better shooter/ better ammo. That's what lead me to order a new barrel for my savage. My basement built AR was more accurate, and more consistent than my Model 11 in an LSS chassis chambered in .308. I've tried about 20 different factory loads with the savage and it's a 1 MOA rifle with me shooting it. I'll give you an example of some groups with my Grendel AR. First one is first 3 rounds ever out of the barrel for sight in (way off target) but consistent.
This is one of my better groups, but I've done this multiple times. Don't have a lead sled so this is all off bipod.
And this is an honest representation of this rifle with factory PPU or Hornady ammo. I can do this all day with this rifle. Maybe not quite half MOA, but I'm happy with my budget 6.5 build.
And my savage continues to be a 1 inch gun, if I'm shooting well.