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Posted: 3/14/2011 12:16:09 PM EDT
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I was at the range today and was getting keyholes with Monarch 55gr FMJ steel case at 50 yards. I thought my scope was off, but when I got closer I noticed keyholing.
What would be the cause of this? I've never had this issue before, and I've shot Monarch quite a bit. I looked down my bore for obstructions but I didn't see anything besides some powder remnants. I haven't cleaned my AR in the last 500 rounds, but that shouldn't be the problem, right?. |
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Try using different ammo. Like some WWB or something American. While I've got nothing against Russian ammo,sometimes their qc can be spotty. Heck tula ammo is what I plink with exclusively.
Try cleaning your bore. If you've got some lead build-up it could cause stabilization issue. Hope you figure it out. |
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Quoted:
Keyholing is a stabilization issue, mainly caused by; improper twist rate, oversize bore or undersize projectile. What are you shooting? If you haven't seen it before our of your gun it's probably ammo related. My answer is based on that... Cheap bullets might have cores that are out of balance. |
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No vegetation.
Barrel has maybe 4k rounds through it over the past 3 years? Barrel is 1:9 non-chrome DTI. I'll try again with different ammo and see how she fares. I shot the other day using Remington UMC with no issues. It's weird because within the same batch I bought, I got some 1.5 MOA 5-round groups with this Monarch. |
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Quoted: I can't recall the round count at which barrels should be replaced for throat erosion, but I'm thinking it's 10K or 20K rounds, maybe more. At 4K, throat erosion should not be causing key holing. Quoted: if you do large volume firing it could verywell be the throat in an unlined barrel.Have the barrel throat gauged to see. How bad can it get after just 4k rounds? I'm not bumpfiring or firing full auto. |
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Quoted:
Keyholing is a stabilization issue, mainly caused by; improper twist rate, oversize bore or undersize projectile. What are you shooting? If you haven't seen it before our of your gun it's probably ammo related. Yea I'd try other ammo and see what happens. |
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