If not too late do look at DPMS service rifle assembled or kit as I got mine, as I had heard before and saw myself on assembly the specs are much tighter than most ,after 8 years of NRA h.p. its still tight ,no loose upper/lower and nothing replaced nut gas ring ,which is a one piece ,not 3 individual rings ,I love it. My gun shoots better than I can with it of course ave. 465 score,bottom line is -tight is good- unless your in a dusty battle zone!
