Just to update: the guy decided to send it back to Springfield for warranty service. Not what I would have done but it is his rifle. I also noticed that there was some defect inside the op rod spring hole. Couldn't see what it was but I couldn't seem to scrape it off with my scriber. I think I would have bought a new op rod from LRB since they came back in stock, tightened up his gas cylinder, and relieved the stock where it was hitting the bottom of the gas cylinder. His other major problem was that the rear hooks on the hammer were stoned too short and the hammer would sometimes drop when the trigger was released. I had a good hammer that I had taken out of my M1 and it worked perfectly in his trigger group, but I put the original back and Springfield can deal with it.