This is the third upper I've built on these barrels, and they are amazing! Great balance and ergonomics, and they shoot like a friggin' shark with a laser beam on its head. With 77g OTM, it'll shoot 3/4MOA all day for me. The intermediate gas system (1/2 way between middy and rifle) is crazy smooth as well, especially with an H1 buffer. I wish Rainier had more of these barrels, but it looks like they were a limited run. I'm keeping one of the uppers, sold the other to my brother, and am offering the last one up to a good home.
Build is as follows:
Rainier commissioned Rock Creek Stainless Steel Match Grade Blank
Twist: 1:8 5R Rifling
Thread Pitch: 1/2 X 28
.625 Gas Block Seat
.223 Wylde Chamber
Intermediate length Gas System
M4 Feed Ramps
Bead Blasted Finish
Weight: 1 lbs. 12.3 oz
BCM .625 low profile gas block, dimpled to barrel
Rainier Intermediate gas tube
A2 Flash Hider
Aero Precision, Anchor Harvey forge M4 upper from Brownells. Has 'murican flag engraved on the top!
No BCG, CH
Geissele/ALG Defense EMR V3 MLOK DDC
I am a factory certified Colt M16/AR15 Armorer and have decades of experience working on the AR platform. I build everything like a life might depend on it one day.
$550 $500 *SPF* shipped/insured. Discreet PP Gift preferred or add 3.5%. No trades. Will not split.