So I built my first AR-10. It's mostly Aero Precision for compatibility reasons, upper (including parts kit), lower (including parts kit), BCG, and carbine buffer kit. It has a Ballistic Advantage 14.5" barrel with a pinned muzzle device. Because it was pinned before I realized I hadn't thrown the barrel nut on there, I am using a Yankee Hill Machine Specter 2 piece gas block (YHM-9378). I put a few rounds of 145gr and 150gr to test it out using both PMAGs and HexMags. In any combination of rounds and magazine, the rifle cycles fine but the bolt does not lock back on the last round. I've manually pulled the bolt back and it does reach the bolt release but there seems to be a good bit of added pressure needed to go from the point where the next round will pick up to where the bolt will catch.
At this point I'm trying to avoid an adjustable gas block. If that's the only true fix, so be it. But I'm civil service and don't make bank so if I can spend that $130 on bills instead of a 2 piece adjustable, I won't complain. I've also read a number of suggestions for a fix. Switch out the 308 buffer spring for a 223 buffer spring. The 223 has tighter coils and I would suspect the buffer tube/bcg wouldn't be able to travel as far back so that would seem like it would make the problem worse. Another suggestion was to take fine sandpaper to the rails on the bcg so it has a bit more room/less friction to travel. But the bcg doesn't seem to have an issue. The other suggestion was to cut a loop off the buffer spring to allow more travel, and slightly less resistance, for the bcg.
This rifle will host a can once it's finally released (8 months and counting so far).
*I realize AR-10 is Armalite and Areo uses the DPMS LR-308 pattern. I'm using AR-10 in the generic.
At this point I'm trying to avoid an adjustable gas block. If that's the only true fix, so be it. But I'm civil service and don't make bank so if I can spend that $130 on bills instead of a 2 piece adjustable, I won't complain. I've also read a number of suggestions for a fix. Switch out the 308 buffer spring for a 223 buffer spring. The 223 has tighter coils and I would suspect the buffer tube/bcg wouldn't be able to travel as far back so that would seem like it would make the problem worse. Another suggestion was to take fine sandpaper to the rails on the bcg so it has a bit more room/less friction to travel. But the bcg doesn't seem to have an issue. The other suggestion was to cut a loop off the buffer spring to allow more travel, and slightly less resistance, for the bcg.
This rifle will host a can once it's finally released (8 months and counting so far).
*I realize AR-10 is Armalite and Areo uses the DPMS LR-308 pattern. I'm using AR-10 in the generic.
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