I have tried two different manufacturers pistol buffer tubes and still have the same problem. Even with the end plate in place, the tube still screws in deep enough to slightly push the buffer retaining pin forward causing a restriction of the bolt closing at the rear. I can close the two halves together by aligning them and then pushing both pins closed together, but I cannot close or open the rear by pushing the rear pin open and lifting the back of the upper. Anyone else ever dealt with this issue? I actually have to back the tube off about 1/8 of a turn to stop the restriction to open or close as designed, but of course I do not want to unscrew the tube everytime I want to seperate the halves as designed. Of course a standard carbine buffer tube works as it should, but I cannot run that option for obvious reasons. I have also contacted RRA to learn if their end plates may be thicker than standard.
Thanks for any replies.