Get this...

sometimes when pulling back on the charging handle, the bolt/carrier gets "stuck" and won't retract.  

It seems to be related to the trigger--if I pull the trigger, this frees up the bolt and it retracts.  It has also occurred twice now when shooting.  

I have a RRA two stage trigger installed.  

Anyone else have this problem?  

Get the instructions for setting/adjusting the trigger and do so, sounds like it's hanging on the disconnect.

There is no adjustment for the trigger.  The RRA triggers are two-stage, 4.5# pull, non-adjustable triggers (unlike a Jewell for example).  

But, maybe the disconnector is fubarred anyway.  I think I'll go back to the GI trigger.  

I had the same trouble with my RR NM trigger.  With the normal take down pin it worked fine.  With the J-P tensioning pin it bound up like you are describing.  I called RR and they told me this:  "You see that very sharp tip on the hammer end, that needs to be stoned down until the hammer will not bind the carrier.  Stone it down with the hammer in the cocked position going parallel to the carrier and remove only .001 to .002" at a time and re try."  I removed .003 inch and it no longer bound.  However, when the carrier was back, there was no play in the trigger so it was still being bound a little.  I removed another .001 inch and now with the carrier locked back I can move the trigger (in the first stage) just a hair, so the carrier is no longer binding the trigger.  By removing that small amount from the top of the trigger you are not compromising engagement as the carrier is still moving the hammer back much farther than it needs to be moved to engage the sear or disconnect, but check as you go and stop as soon as you stop the binding.  Do not use a file as you will remove too much, only use a fine stone and it doesn't take more than a few passes.