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GM-M16 20" M16 A2 5.56mm w/Ext. 1:8 twist

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Product Description

M16A2 5.56mm, 20", 1:8 twist, 41V50 steel, weighs 2.05 lbs., fully machined and assembled with extension (M4 feed ramps), chrome line bore and chamber, .750" gas block, designed for rifle length gas system, drilled gas port, phosphate finish,button rifled, air gauged, stress relieved, muzzle thread 1/2 x 28.

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

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Product Reviews

Showing reviews 1-5 of 33 | Next

  1. pencil barrel 4 Star Review

    Posted by on 5th Jul 2018

    haven't shot this yet but i'm concerned how thin it is before the gas block. it's nice that it is light but i'm wondering if it's going to string shots once it gets hot.

  2. great barrel 5 Star Review

    Posted by on 17th Jun 2018

    I used this to build a standard A2. It’s just a range toy, but it’s very accurate and I like the light weight of the government profile. I would definitely buy from green mountain again.

  3. Very nice. 5 Star Review

    Posted by on 23rd Apr 2018

    Excellent well made and fast shipping. Have not had a chance to try it yet but will soon. Thank you GM.

  4. 20” 5.56 1:8 twist 5 Star Review

    Posted by on 16th Apr 2018

    Excellent barrel. Hands down best for the money. Sub MOA accuracy with bulk ammo Will definitely buy another and recommend it 100%

  5. what i expected and more ! 5 Star Review

    Posted by on 1st Jan 2018

    I have had green mountain barrels on black powder rifles for a long time and was in need of a barrel for my new AR build . So I turned to green mountain and couldn’t be happier . I shot it today and this gun is a tack driver ...... if you are in need of a great quality barrel this is the one for you !

Showing reviews 1-5 of 33 | Next