I've got an M1 Garand that was rebuilt and rebarreled 3360 rounds ago that now gages a "4" in the throat and a "2" in the muzzle. I used to shoot in CMP & ATC matches, but I haven't used this rifle for matches in nearly two years due to decreased accuracy. I've tried various patches and tested them with careful slow fire.
Yesterday I cleaned the barrel, disassembled, cleaned, greased, and reassembled the rifle. Today I took it to the range to get a 100 yd. zero with a load I've only shot once before in preparation for a fun type shoot tomorrow. The load was nothing particularly odd, but I had only shot it once before, and it gave reasonable results. The load was the 150 gr. Remington PCLSP seated to 3.215" OAL (approximately 1/2 of the crimp grove into the case mouth)/48.0 gr. IMR4064/LC cases/CCI No. 34 primers. Previously my best load was a 168 gr. Hornady or Sierra with 45.0 - 46.0 gr. H4895 and the same cases and primers.
First I fired ten shots from a bench at a SR-1 target at 100 yds. The first two shots were single loaded, and the last eight from a clip. I fired slow enough to check each shot through a spotting scope before firing the next. The group was truly awful and also required a sight adjustment of three clicks left and two clicks down, which I made. The group scored 83-1X.
After making the sight adjustment I raped fired an eight-round clip from the bench to confirm the sight adjustment. The adjustment was spot on and as good as it could be with 1 MOA adjustments. The eight rounds scored 76-1X/80, or 95%. I was shocked an puzzled why the rifle shot this well.
I'm open to any answers that involve rifle or shoot problems, but I really don't think I have an ammo problem out to 200 yds.
