02-17-2019, 02:59 AM
Hello all! New to the Grendel world after the better part of a year of research. I built a lower receiver from parts, and elected to purchase an Aero Precision upper with a 20" barrel, rifle-length gas system.
I had an issue right out of the gate with crazy marks on the case (shooting factory Hornady Black to break in the barrel) that I would otherwise think were pressure-related. Ejector circles with burrs raised up, large extractor gouges on the case head, etc. These have been fixed so far with the addition of a JP adjustable gas block.
I'm still getting some major dents on the case mouth, that appears to be from impact with the deflector. I've been doing lots of reading and searching here on the forum...is this the circumstance where I'd need to trim the extractor spring? I have polished the extractor itself which did cut down on the extractor gouges.
Looking forward to continued learning here!
I had an issue right out of the gate with crazy marks on the case (shooting factory Hornady Black to break in the barrel) that I would otherwise think were pressure-related. Ejector circles with burrs raised up, large extractor gouges on the case head, etc. These have been fixed so far with the addition of a JP adjustable gas block.
I'm still getting some major dents on the case mouth, that appears to be from impact with the deflector. I've been doing lots of reading and searching here on the forum...is this the circumstance where I'd need to trim the extractor spring? I have polished the extractor itself which did cut down on the extractor gouges.
Looking forward to continued learning here!