RF Upper 16" 5.56 M4 profile RF Quad Rail: FQR 12" rail
RF Upper 16"  5.56 M4 profile RF Quad Rail: FQR 12" rail

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MSRP: $259.95

Stock Status:(Out of Stock)
Availability: Current Production Time Up To 4 Weeks
Product Code: FU16-5.56M4-12FQR

***Please select your options on the right hand side for BCG, Charging Handle, and other choices***

The Radical Firearms M4 Upper Receiver is a flat top, law-enforcement grade, drop in receiver, ready to be mounted to any MIL-STD AR-15 lower receiver! This fully MIL-STD compliant receiver provides a high-quality upper for any level budget or shooter. Comes complete and assembled with Upper Receiver, Forward Assist, Ejection Port Door, Barrel Nut. 16" M4 Profile Barrel and A2 Flash Hider. Bolt Carrier Group and Charging Handle are additional and are offered at discounted prices in the drop down menus.

  • 16” 4140 Chromoly Barrel With Melonite Coating
  • 5.56 M4 Profile
  • M4 Feed Ramps
  • 1:7 Twist Rate
  • A2 Flash Hider
  • 1/2x28 TPI
  • Low Profile Gas Block
  • Carbine Length Gas System
  • Radical Firearms Forged MIL-STD Upper Receiver
  • MIL-STD Upper Parts Kit
  • RF Dimpled Forward Assist
  • Radical Firearms 12” FQR
  • Quad Picatinny Rails The Full Length of the Rail
  • Made in Houston, Texas U.S.A.!

Average Rating: 5 of 5 Total Reviews: 2 Write a review »

  0 of 0 people found the following review helpful:
Great Upper November 29, 2016
Reviewer: -D from Manhattan, KS United States  
I've had this upper for about 6 months now and I'm very happy with it. Quality seems great, fits my lower without problems and functions perfectly so far. I will note I purchased mine with the Fail Zero BCG, and it runs like butter in the upper. Very happy about my purchase.

I haven't had any problems with my guardrail, although I know some people have had issues with theirs coming loose. I'm was originally planning on hitting the hex screw with loctite but unless mine start to come loose, I'm happy with how they came from the factory.

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  0 of 0 people found the following review helpful:
Very nice upper for the money August 3, 2016
Reviewer: R from Jamestown, RI United States  
Took exactly 8 weeks to ship, so be patient... Came well packaged and had no manufacturing or shipping damage.  The Radical upper is a tight fit on my U.S. Autoweapons lower, and the finish matches  perfect. Slapped a Bearing 3x prismatic on it, sighted it, and burned 100 rounds of Ultramax 55gr .223 through it with no errors the first time out.

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