After todays range trip, I had a whole slew of malfunctions with my rifle build. I will try to get some photos up later this evening, but here is what is happening:
First off, I'm having a hard time seating the magazine with the bolt closed. I have 3 G2 Pmags, happens to them all.
Secondly, if I load the rifle with bolt open, I will be able to shoot 2 rounds. The 3rd one clicks. Upon extraction of the bullet, small to moderate effort to pull the charging handle back, the brass has 2 gouges on the top and the primer isn't touched, so I can assume I am not achieving full battery. I'm thinking this is from the bolt closing on top of it while chambering the last round that fired.
One of my malfunctions jammed a round in the feed ramp (M4) resulting in bullet setback.
So I've got a bit of a mystery for me here. This never happened with my factory Stag.
The lower is a Blemished San Tan Tactical with a CMT UPUR-1LH on top. There is a little wobble from the STT lower that doesn't exist when the upper is mated to one of my other forged lowers. I do have an adjustable gas block, which I will open all the way up next session. I am using a heavy buffer, and the barrel is an 18" SPR with a rifle length gas tube.
Thanks for the help. Once the kids are fed and in bed, I can get some pics up.