Stirling XD
New member
I had a spare Rock River upper that I decided to convert to a 6.5 Grendel. I bought an 18” AR Stoner a barrel (Grendel II) and bolt from Midway. The first 12 shots worked well. Then I started having failures to eject that progressed into failures to extract. The bolt would also try to load a fresh shell. I cleaned everything thoroughly and continued having the same problem. The bolt just would not pull the spent shell out of the chamber.
I removed the gas block and tube and can't find any problems. And since the bolt locks on an empty mag, I think my problem is elsewhere.
I decided the replace the extractor spring with a heavier one and added an O-ring. The next trip to the range went much like the first. The first 10 rounds fired fine, but by the time I got to round 25, the only way to remove the spent shell was with a cleaning rod. It was still trying load a fresh round. The bolt always locked open on an empty mag. I am shooting Hornady Amax 123 grain ammo.
Based on some of the other posts I’ve read, I may need an adjustable gas block. But I’d like to get some other opinions. I’m also wondering if I may have a defective bolt or barrel.
I removed the gas block and tube and can't find any problems. And since the bolt locks on an empty mag, I think my problem is elsewhere.
I decided the replace the extractor spring with a heavier one and added an O-ring. The next trip to the range went much like the first. The first 10 rounds fired fine, but by the time I got to round 25, the only way to remove the spent shell was with a cleaning rod. It was still trying load a fresh round. The bolt always locked open on an empty mag. I am shooting Hornady Amax 123 grain ammo.
Based on some of the other posts I’ve read, I may need an adjustable gas block. But I’d like to get some other opinions. I’m also wondering if I may have a defective bolt or barrel.
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