06-23-2012, 08:43 PM
Well, your extractor works!
Load is clearly too much for your system, so back down. You should also look into a heavier buffer. Did you say you have a RRA "CAR" complete lower? Like with a telescoping stock?
If so, you probably have a 2.9 oz buffer. While they work with a lot of carbines and factory ammo, I only use H2 and H3 buffer weights, considering pushing 123gr bullets.
The military buffer, recoil spring, gas port, dwell time, and bolt carriers are meant to push 55gr-62gr pills at high pressure, and they use a bolt carrier that is heavier than the RRA AR15 carriers. That gas ports are cut to offer reliable operation across the temperature range.
Was your recoil spring used in a 5.56 gun before going Grendel, and if so, for how many rounds? They need to be replaced once a certain round count or minimum length has been breached.
Load is clearly too much for your system, so back down. You should also look into a heavier buffer. Did you say you have a RRA "CAR" complete lower? Like with a telescoping stock?
If so, you probably have a 2.9 oz buffer. While they work with a lot of carbines and factory ammo, I only use H2 and H3 buffer weights, considering pushing 123gr bullets.
The military buffer, recoil spring, gas port, dwell time, and bolt carriers are meant to push 55gr-62gr pills at high pressure, and they use a bolt carrier that is heavier than the RRA AR15 carriers. That gas ports are cut to offer reliable operation across the temperature range.
Was your recoil spring used in a 5.56 gun before going Grendel, and if so, for how many rounds? They need to be replaced once a certain round count or minimum length has been breached.