Great upper - Radical Firearms 16 in. 300 AAC Blackout Upper Assembly

It came coated with something,took apart rail and cleaned and oiled upper good, and reassembled,and added a Toolcraft BCG & a charging handle. The gas block screws are torqued very tight, so I left them alone. Added to my carbine lower, and I shot about 60 rds of ammo threw this upper, and it ran like a sewing machine. It likes the Ammo inc. 110gr V-Max bullet, that was only ammo I had to shoot at that time Great upper at a dam good price, with a CMV Nitrite treated 16" barrel, very accurate at 100 yards, very little Recoil. The deal of the Century. Get one, I recommend. My favorite gun for brush hunting in Texas.