12-24-2011, 03:48 AM
What mags are you using? If 17rd CProd, try 10rd or 25rd. You might also need to send it back with the full explanation. Sounds like you have a gas system issue from your post, but who knows. I would look at the alignment of the gas block, and determine what material it is. I avoid Aluminum blocks for this reason, but I don't think AA uses them either, and they usually loc-tite their gas blocks.
Also, if you haven't, properly lubricate your upper with Slip2000 along with bolt carrier raceways, cam pin hole, and lightly on the outside of the lugs. A dry AR15 does not usually run, but since your Sabre runs, this might be negligible.
Also, check that your gas tube isn't binding against the carrier key. With those loads, you should have very positive lock, even with milder charge weights.
Also, if you haven't, properly lubricate your upper with Slip2000 along with bolt carrier raceways, cam pin hole, and lightly on the outside of the lugs. A dry AR15 does not usually run, but since your Sabre runs, this might be negligible.
Also, check that your gas tube isn't binding against the carrier key. With those loads, you should have very positive lock, even with milder charge weights.