AR BULL BARREL Accuracy
I have an AR old slick side upper that I installed a RR 24" .223 wylde bull barrel on. It is ss with 1x8 twist. It is heavy!!!! The carrying handle has been machined of and a weaver flat top style mount bolted. If you look at it from a few feet away, it resembles a flat top. It has an accue wedge and I also lay a piece of tape between upper and lower to force a tight fit. The gun will not consistently shoot accurately. I am a stickler for accuracy and I wanted to build a super varmint rifle. SUB MOA is demanded. I have a 15 x Leupold older LPS mounted on it. I have tried combinations of H4895 and IMR 8208 and wasted 500 + 69 gr SMK bullets. Working up loads, I have digital scale and Redding match powder thrower. I get no bullet run out, which is startling to me. But I have gauged them. My 30-06 is another story. I have to adjust every bullet. Nonetheless, I get excellent groups during one range event and then come back with a whole bunch of the best loads from the first trip only to sling them all over paper and have the group shift a couple of inches. Group shifting is horrible. Mind you, I always shoot this rife at 200 yds and make sure no wind. Loads go from 1" groups to 2 1/2 " groups and may be 2 inches low or high from previous trip. A fellow at the range suggested that it might be that the barrel is just too heavy for the receiver and any excess pressure from me on rifle/stock/grip from magazine back might be causing inconsistencies. I even go so far as to sort and weigh Winchester brass for this rifle . Any recommendation of any who have built this type rifle and experienced the same problems????