[ARCHIVED THREAD] - Bushmaster keyholing

Posted: 6/26/2012 3:27:48 PM EDT

I just bought a like new, unfired bushmaster hbar 1/9 twist carbine upper on the EE. I bought some ultramax 52 gr. hollow point to shoot and test the gun out.

at 25 yards my rounds were keyholing occasionally, and i don't know what to blame. My suspicion is that if the barrel is not out of spec, it is bad ammunition.

any advice?

Posted: 6/26/2012 3:33:12 PM EDT

[#1]

bad ammunition

Try something in good quality and heavier projectile.
It may like 55 gr, it may like heavier....

Posted: 6/26/2012 5:56:37 PM EDT

[#2]

Also check the crown and look for bullet strikes on the FS.

Posted: 6/26/2012 7:56:16 PM EDT

[#3]

Update: tried some federal 55 grain fmj, and there were zero issues.

Posted: 7/6/2012 9:54:42 PM EDT

[#4]

The only time I ever had an issue with keyholing was with a 11.5" 1:9 Brl shooting 55Gn TAP. No real reason other than that brl didnt like that load. Everything else worked fine.

Try different ammo.

Posted: 7/7/2012 6:37:41 PM EDT

[#5]

Take off the flash suppressor and test.. If no key then either drill out the bore or replace..if still getting keys then checknthe bore and or anything hitting the round on the way out, also bad ammo keys,,,,

[ARCHIVED THREAD] - Bushmaster keyholing

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[ARCHIVED THREAD] - Bushmaster keyholing

[ARCHIVED THREAD] - Bushmaster keyholing