I bought one brand new about 2 years ago that I no longer have, had it less than a week. It had the same problems and DPMS seemed really less than interested, as you say tighten this, adjust that. At one point I discovered that the gas block was loose and I thought I had figured it out, nope! Now, my opinion, a brand new gun is not my responsibility to adjust and tighten. It should function. I took mine back to the dealer for a full refund. That was my first and only experience with DPMS. Although I would love to have one of the SASS rifles from DPMS I think the same guts inhabit both. I now shoot a Armalite AR-10 and the difference between the 2, both brand new is amazing. In 100 rounds I have had 2 failures to fire and both were ammo related duds.