Hey guys,
    Shooting my LWRC tonight, piston operated, and had this happen:

15 shots, no problem
on the last shot the bolt "stayed open", as it should.............right..........but, it was NOT the bolt hold open keeping it open.    When you pull the charging handle back, and release the bolt is pulling back 1/4" and then when released, it comes forward 1/4", and then impacts something hard internally.....metal to metal sound.     It will not come forward, so I can take it apart.     It is jammed in this 90% rearward position, so I can't even take it apart to look for obstructions.     I was shooting suppressed, so I know the pressures are greater, but don't know if that is what caused this.     Only way I know to "try" to take it apart, is to take the lock nut off of the buffer tube and take out the buffer/buffer spring........but, if the bolt is impacting something internal, I'm not sure that taking the buffer/buffer spring out will do anything..............

anyone encounter this scenario??

thx
Jordan

Did a casing get lodged above the BCG in the charging handle channel?

A dislodged primer can do varied nasty things.

This. Sounds like a bolt override. Look into magwell and see if brass is stuck between charging handle and bolt carrier group. If so, just take your finger/s (through magwell or ejection port) and press the BCG backwards, and shake the gun if necessary. Should get the suspect brass to fall out.

Sounds like something stuck in your BCG or your gas key is jacked up. I would take the buffer tube off and go from there. But what do I know I have a low post count. This is why I do not stake my castle nuts. I have never had one loosen up before.

AL