czerr3@gmail.com

Thx a lot for the lube advice. Ill be sure to soak it down next outting. Will get the suggested measurements back here during the week.

Oh and @98Z5V No its not Wet. Its adequately lubed as I do all my other firearms just not over done and sopping wet.

Rifle Length gas tube with a YHM Gas Block. 20" Faxon Barrel. Geissele flat spring AR10 buffer spring. Aero AR10 Buffer. Fail Zero NiB BCG. I don't think its under gassed as it completely ejects the 1st round, picks up and seats 2nd round. It simply doesn't lock down the bcg the final 1/16". If I load and shoot only 1 round, it fires, ejects and locks open the receiver. So I'm thinking not heavy enough ammo or the mags are slightly rubbing my bcg.

Sorry for my ignorant what are you indicating by "Wet" ? And had to order a new HS field gauge on Miday, will arrive Tuesdsy.

Tried Pmags, AR Stoner, Hexmag, ASC. Any other type suggestions?

Racking the bcg for 1st round seats perfectly. Only the 2nd round gets picked up and moves into the chamber but not far enough to lock in. Could it be the mags?

Steel barrel nut for a free-float handguard.

Have run only about 50 rounds due to pure frustration after all the attempts to resolve the failure of the 2nd round to fully seat and lock in the bcg completely. Have not confirmed headspace so may need to be the next step.

After 1st round firing, bcg ejects 1st round and strips and loads 2nd round. However bolt doesn't go fully into battery. About a 16th if an inch from full battery. I've changed buffers and buffer springs multiple times. Changed BCG to a NiB one. Started with Gene3 PMAGS, than to AR Stoner brand, Hexmag and metal Mil-Spec mags. Still a no go. Upper and lower are both Aero. Can't figure what to try next.