M16 A1 5.56mm, 1:12 twist Rifle Barrel, 20" 41V50 Vanadium alloy milspec steel, fully machined and assembled with extension, chrome lined bore and chamber for optimum performance and durability, drilled gas port, phosphate finish. 1960s era M16 A1 pencil profile with traditional m16 feed ramps, muzzle threading 1/2 x 28, weighs 1.75 lbs. This barrel is phosphate (black in color). Barrel is not pinned for front site.
Under "See 1 more picture" there is a detailed drawing of this barrel.
Posted by Rick on 11th Aug 2016
Just finished installing the A1 barrel in a retro build. Excellent accuracy with 55gr FMJBT loads from several manufacturers. Very pleased with the barrel. It's made the build worth the time and expense!
Posted by Stuart on 6th Aug 2016
This Barrel is amazing can not believe the quality. Installed this barrel on a custom built ar. With a free floated barrel the accuracy of this barrel is insane. Will be buying all of my barrels for future ar builds from green mountain barrels. Great job green mountain keep up the outstanding work.
Posted by SJW on 1st Aug 2016
The finish quality on this barrel is superb. Way better than the original Colt.
Posted by A on 27th Jul 2016
Completed my M16A1 parts kit build with this barrel. Looks great and functions as expected.
Posted by Unknown on 27th Jul 2016
Working on 601 clone.This GM barrel was as close as I could find. Have the same one on an a-1 from Century and another on a a-1 kit build. No problems,great performance. Thanks Green Mountain.