Grendel loading

My shooting buddy shoots a grendel with a 20" black hole weaponry barrel 1:9 and shoots 1/4 to 1/3 moa consistently at 100yds with 123 eld and varget in some hornady cases.
 
Perhaps it was our barrel but we couldn't get our Grendel to shoot Berger 130 ar. Or the 140 hunter elites very well. I think lighter is better