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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.

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

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  1. great barrel 5 Star Review

    Posted by on 12th Apr 2016

    Barrel came neatly packaged. Ran a single cleaning patch down it and installed. Holds 3/8" groups at 100yds shooting 60 fmj by. Very very pleased

  2. worth the money fore sure 5 Star Review

    Posted by on 4th Apr 2016

    Barrel installed flawlessly, finish was perfect, chrome lining looked great, headspaced correctly, gas port was free of obstructions, went to the range and out shot many scoped rifles at 100yds with standard mil-spec carry handle sight, no ejection issues, shells had no deformations/ imperfections, price was right, why are you not clicking the add to cart button? I own the 16" carbine barrel and have had the same results. Only thing I wish was different on the m16 barrel was that I think it should be offered with the pin on sight. But seriously great products and customer service, product showed up packed well and on time. Also got a free green mountain barrel sticker

  3. Impressive quality and impressive price 5 Star Review

    Posted by on 2nd Apr 2016

    Note: If you're on this website, considering a Green Mountain barrel, stop hesitating over the $50 difference from a cheap hammer forged barrel, and just get the Green Mountain. It's not even close.

    I just got back from the range. The barrel is well worth the money. I can't remember ever having a tighter group from an AR. Even the shots that I rushed fell within the group. (fired about 110 rounds) This barrel is very impressive. 20" barrel, used on: 15" tube handguard, Aero Precision upper, Rock River lower, Anderson lower parts kit, mil-spec M4 buffer/tube, used both a mag-phos BCG and my cryptic coating black BCG. Very cheap scope, and a bipod. I was amazed at the consistency, especially given the windy conditions (target was often moving) and I'm not a competitive shooter at all.

    The delivery was very fast, even at standard ground. The packaging was top notch. The parkerizing is as smooth as anodizing. Very impressed with GMRB Co. Looking forward to trying something a little different, maybe fancier, on my next build.

  4. great piece 5 Star Review

    Posted by on 21st Mar 2016

    Can't wait to put some rounds thru it! Barrel shows a great touch of craftsmanship and I am confident the performance will be just as good.

  5. good product 5 Star Review

    Posted by on 23rd Feb 2016

    fast shipping

Previous | Showing reviews 6-10 of 29 | Next