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GM-M15 20" M16 A1 5.56mm 1:12 twist

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Product Description

5.56mm, 1:12 twist, 20", 41V50 steel, , weighs 1.75 lbs., fully machined and assembled with M16 extension, chrome line bore and chamber, drilled gas port, phosphate finish, button rifled, air gauged, stress relieved. 1960s era pencil profile, muzzle threading 1/2 x 28.  

Barrel is not pinned for front site.

Under "See 1 more picture" there is a detailed drawing of this barrel. 

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Product Reviews

Showing reviews 1-5 of 72 | Next

  1. Top quality barrel. Excellent workmanship. 5 Star Review

    Posted by on 22nd Jul 2018

    Use this barrel on a varmint rifle. Hornaday 55 grain SPSX and 40 grain Nosler Varmageddon Handload ammo. Accuracy is excellent.

  2. Appreciated 5 Star Review

    Posted by on 7th Jul 2018

    Having an M16-A1 era rifle from the 1960s/70s, Breathtaking. Being able to find original part, Outstanding. GreenMountain Rifle Barrel Co. Thanks.

  3. A great product! 5 Star Review

    Posted by on 20th Apr 2018

    Excellent product and fast shipping!

  4. 1 in 12 ar barrel 5 Star Review

    Posted by on 27th Mar 2018

    Great! Came quik.

  5. Superb, that is why I bought 3 more! 5 Star Review

    Posted by on 27th Mar 2018

    I purchased one of these barrels a couple of years ago. It was going to be a "plinker." It turned out to be so accurate that I ended up building a light weight match rifle from it. Last year when these barrels were on sale I though I would get another one just to have on hand when a project came up. I waited too long and they went off sale :-(

    For 6 months or so I checked the web site every morning until I found the barrels on sale again. I purchased 3. Not sure what I will build with them but it is better to have and not need than need and not have :-)

    Bottom line an excellent barrel with I would buy again, and did!

    p.s. I do wish they had been available with M4 extensions. True the M4 cuts are not really needed on a rifle length barrel. Problem is that so many upper receivers these days have the M4 ramps.

Showing reviews 1-5 of 72 | Next