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

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Product Description

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. 

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Product Reviews

Showing reviews 1-5 of 63 | Next

  1. Beautiful Bore and Finish 5 Star Review

    Posted by on 27th Apr 2017

    I work for Windham Weaponry, a stone's throw from Green Mountain's facility in New Hampshire. I received the barrel and we went through it with our bore scope to look at the interior. Wow! The free-bore and rifling were perfect and consistent, and the chamber was excellent, no rings, contacts or pitting anywhere! The chrome throughout the chamber and bore was consistent and smooth. I am using this for a retro-build M16A1 look-alike. The only wish I have would be to have the barrel at least cut for taper pins for a .625" gas block. I imagine Green Mountain doesn't do this incase a customer wants to use a low profile gas block with set screws or other styles. Overall, an extremely well made product that I highly advise anyone to use if doing a retro build or using it as a varmint rifle.

  2. Great Product ***** 5 Star Review

    Posted by on 11th Apr 2017

    While looking for a barrel for my M16 retro build I ran across an ad about a guy who bought one of GM 20" barrel, he compared it to one of his Colt built barrels and said the Green Mountain looked to be a better made barrel. All though I'm no expert the 20" Green Mountain barrel I bought is well made.

  3. A well made barrel 5 Star Review

    Posted by on 1st Feb 2017

    Wanted to build a retro A1 Vietnam style AR and was happy to find the barrel I needed for my project at Green Mountain. Authentic, well made and accurate too.

  4. Excellent product 5 Star Review

    Posted by on 30th Jan 2017

    Recently purchased an A1 barrel for a retro build. Outstanding service and barrel looks and performs great. Installed on my old Colt kit with no problems. Highly recommend Green Mountain to anyone looking for a quality product at a fair price.

  5. M18 Barral 5 Star Review

    Posted by on 25th Jan 2017

    I am probably one of the few people who have a NOS M16 surplus barrel, had it for over 20 years. The Green Mountain Barrel I just received is not just a Repro., it is a far more high quality part which makes the original Colt barrel look not so great as it did before! The GM barrel has nicer machining and most likely is the same as the first production M10 barrels where. The Chrome bore and rifling could be no better. The price is very low for a part so nice.

Showing reviews 1-5 of 63 | Next