07-26-2020, 10:38 PM
shreddykruger Wrote:I just built a 18 with a criterion barrel and its been super problematic so far. Ive even called criterion about it and they recommended trying a Jp enterprises bolt since thats what they use for setting headspace so we will see. If not they said go send it in. It seems to be getting better but is nowhere near where the 20 ballistic advantage one in my other gun is at. Ill be able to get past 200 again tomorrow so fingers crossed on that one. Hopefully you find a good load for yours but I figured I would mention my troubles.
Having done this I would prob not go less than 20 next time and stay with rifle length gas. Its such a more enjoyable gun to shoot for such a small difference
My 20 seems to like120 grain smk with 28 gr of tac and standard match primers in starlike brass. My tests last week with 28,28.5,29 had the best groups at 28.
Going to try same weights and bullets tomorrow with cci 450 and compare to the 28 grain loads that I have left over after shooting prs. Had no pressure signs at 29 gr so hopefully they are ok with the 450s
I had to return my 18" Criterion hybrid barrel. I couldn't get it to shoot any better than 2.5" groups if I was lucky. I tried several powders and bullets with no luck. Factory ammo produced 4" groups. Luckily Brownells took it back after I had it almost two years. Head space was really short.

