Gun is an Aero Precision 10” barrel. I worked a load up from 15-17.5 of H110 with 155 Berger hybrids. 16.3 and 16.5 looked like this group. Everything else was 5” plus. I loaded 20 up at 15.4 and shot 3 shot groups letting the barrel cool between groups. Every time the second shot is getting thrown and the third comes back beside the first. What could be causing this? I tried less crimp and it was allot worse.
- Thread starter jsthntn247
- Start date
I stopped crimping all together just to take that factor out of the equatio, I have zereo problems shooting subs and 125 Sierras
Are you using a chrono? If so, is it hanging on the barrel?
Seems odd it’s pattern of always the second shot but could be coincidence and hotter load. If chrono is on barrel it could throw it off, though that seems really far off.
Seems odd it’s pattern of always the second shot but could be coincidence and hotter load. If chrono is on barrel it could throw it off, though that seems really far off.
No chrono on the barrel
Might be worth trying 5 rd group.
1st round chambers differently then subsequent rounds.
Last round has no pressure on bottom of BCG.
Both 1st and last round out of an AR have potential to be out of core group. Typically I've not seen the drastic difference you are seeing but I am curious to see what a 5 rd group looks like of the same ammo.
Pistol port or CAR gas system?
Buffer weight?
Suppressed or unsuppressed?
Any other propellants on hand in correct burn rate? If yes, what propellants are available.
1st round chambers differently then subsequent rounds.
Last round has no pressure on bottom of BCG.
Both 1st and last round out of an AR have potential to be out of core group. Typically I've not seen the drastic difference you are seeing but I am curious to see what a 5 rd group looks like of the same ammo.
Pistol port or CAR gas system?
Buffer weight?
Suppressed or unsuppressed?
Any other propellants on hand in correct burn rate? If yes, what propellants are available.
There was a thread on this a couple years ago. Had something to do with the way it was feeding from one side of the magazine. Pretty sure it got solved. But I don’t remember the name of the thread. Cheers
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