03-11-2022, 04:48 AM
Is it safe to assume you are running a fixed gas block or an AGB fully open? What powder are you you using? Your pressure is probably really dropping off by the time it hits that R+2 port if it's a fast powder - or maybe it's slightly misaligned. Or maybe the Proof ARC barrels are really optimized for heavier bullets. 70's might be worth a shot before 87s. I do them just shy of 3k in my 24" 6x45 and they are automatic on P dogs to 400. 3100 should be well within reach for a 20" with a temp stable powder like Benchmark or XBR.
#FJB