Burks194

By mil spec I mean the parmeters of a factory lower per various searches. With one round it will lock back and two it will lock back but the third hangs up. The jam/hang up is what I would call a half chamber. Gas system is rifle length. Parts are midway cheapies. Barrel and extention are Anderson. BCG was from Primary Arms and dont remember the brand. To late to fire the weapn to get a picture. I'm just baffled why two rounds fire flawless and eject but the third fails to chamber/half chamber. Tried various brands of rounds with the same results so thats why I'm perplexed.

Hello all new to this forum. My problem is this. I milled an 80% lower and it works as so, but when married to a raw/blonde upper receiver with an A2 buffer tube/spring kit using a nickel boron BCG on a 18" barrel with non-adjustable gas block.....it fires 2 rounds flawless but the third fails to fully chamber, every time with a plethora of rounds. Everything is properly lubed. I have built several rifles in the 5.56 and 204 variety but this is my first 80% lower build in the 308 variety. I thought it was the lower but everything was milled to mil-spec and checked twice. I'm at a loss and refuse to proceed any further till this issue is resolved. Please help. I am very inclinded with my hand and tools. Just need a good starting point. Thanks