Thanks for posting this. I got the exact upper you have for Christmas and just this Friday had a chance to shoot it with a scope mounted. I didn't get the accuracy results that you did, but I'll be the first to admit I am most likely the limiting factor. Shot both Black Hills 69gr OTM and Prvi 75gr OTM with the BH shooting just over 1 MOA 5 round groups and the Prvi right around 2 MOA.
What kind of mount and optic are you using?
“The ruling class doesn’t care about public safety. Having made it very difficult for States and localities to police themselves, having left ordinary citizens with no choice but to protect themselves as best they can, they now try to take our guns away. In fact they blame us and our guns for crime. This is so wrong that it cannot be an honest mistake.” – former U.S. Sen. Malcolm Wallop (R-Wy.)