Here is today's group report.

Test Sat March 9, 2002. A2 style after a rechamber to 5.56 match for reliability sake.
All groups at 100 yards off of front and rear bags with a 12 power scope and aimtech mount (the cheap aimtech mount has in the past held better than the ARMS model)
All were 5 shot groups, and I am reporting total size and closest 3. I used a sewing ruler and measured from the start of one hole to the start of another. 1/8 was a close as I could get, so I rounded up or down as seemed correct.
The gun had liked ultramax with the nosler bullets, but I was out of that today. Wind was calm, temps in the low 50s, just when I was bringing the target stand in was when the big storm front hit.


3 shots all 5 shots
Q3131A
1. 1” 2 ½”
2. 1 ½ 2 ½
3. ½ 1 ¼

IMI 855 ball
1. 1 3/8 3 ½
2. 7/8 3 ½
3. 5/8 1 ¾

PMC mid 80s 55 gr ball
1. 1 ½ 2 3/8
2. 1 ¼ 2 1/8

Black Hills 55 gr FMJ
1. ¾ 1 5/8
2. 1 ½ 1 ¾

Federal prem 55 gr Sierra gameking BTHP
1. 7/8 1 ¾
2. ¾ 1 ¾


What should I try next? I can see a trend with the more expensive stuff.

You can try some Black Hills 69gn BTHP.