Taking good advice from the Forum I got some Black Hills match ammo, along with some cheap stuff, to test in my Armalite with a 20" 1:8 .223 Wylde.
Of course it was the expensive stuff that shot the best.
.85" center to center (including the flier) at 100 yards off a sock stuffed with pinto beans:
Details on the gun and ammo to follow.
69 Match King HP