He has not said anything, so everything is good. But if its not a flaw I would like to have changed how far back the hammer pulled. Be sure to only put .20 gram BB's or greater as .12 BB's will most likely break in the chamber of the gun and jam it all to hell. Tech Sight's TS155 tool for Adjusting TSR100, and AR-15 M16, rifle sights. I had to pull the hammer down even more to dislodge the slide. UHC model UA-939.