AR-15 Upper Assembly – 16″/ 5.56 / 1:8 / 12″ CBC Arms Keymod AR-15 Handguard / Rail

Icon - 5.56 NATO AR CaliberIcon - 1:8 Twist RateIcon - 16 AR Barrel
(8 customer reviews)

This AR15 upper receiver assembly comes ready to attach to any Mil-Spec lower receiver. It is built around a 16 inch, 4150 chrome moly barrel and has a black nitride finish. The upper receiver is a forged M4 flat top upper, allowing you to easily attach rifle scopes and red dot sights to the picatinny rail.

$299.00 $199.00


Stock Status: Available for Immediate Production


This AR15 upper receiver assembly comes ready to attach to any Mil-Spec lower receiver. It is built around a 16 inch, 4150 chrome moly barrel and has a black nitride finish. The upper receiver is a forged M4 flat top upper, allowing you to easily attach rifle scopes and red dot sights to the picatinny rail.


Outfitted with a 12″ Keymod Rail that features strong attachment points for accessories resulting in accessories and optics having an excellent return to zero capability when detached and reattached. The rail also features a full-length picatinny top rail that sits flush with the upper receiver and has anti-rotation tabs to keep it locked in place. This upper assembly comes with a standard A2 flash hider that effectively suppresses muzzle flash and protects the 1/2×28 barrel threads if you are planning on adding a muzzle break in the future.

  • Barrel: 16” 5.56 Melonite Barrel Chrome Moly
  • Twist Rate: 1/8
  • Feed Ramps: M4
  • Gas Block: Steel .750 Low Profile
  • Gas Tube: DGI Stainless Carbine-Length
  • Muzzle Device: Steel A2 Style Flash Hider
  • Rail: 12″ CBC Free Float Keymod Rail
  • Upper Receiver: Forged Upper Receiver
  • Upper Components: Mil-Spec Forward Assist, Mil-Spec Dust Cover, and Brass Deflector

Product Details: AR-15 Upper Assembly – 16″/ 5.56 / 1:8 / 12″ CBC Arms Keymod AR-15 Handguard / Rail

➲ Upper Receiver

The foundation of all good AR\'s is built upon a dependable upper receiver. CBC upper receivers offer best-in-class quality while providing you years of dependable service. Boasting a MIL-SPEC type III hard coat anodized finish and machined from 7075-T6 forged aluminum, this M4 flat-top receiver delivers a lifetime of superior function. You want your AR built upon a solid platform - this receiver gives you the confidence that your AR-15 will function when it counts most.

➲ Carbine Gas Tube

An essential component to your AR15 is the gas tube, which keeps your build up and running. This gas tube is constructed from corrosion resistant stainless steel ensuring a lifetime of service.

➲ .750 Low Profile Gas Block

The gas block is a critical link in the chain that is too often overlooked. This component ensures that your AR runs reliably. Made from high-quality steel with a smooth nitride finish, this gas block is efficiently designed to stay put with the percussion of gunfire. With its low profile this gas block allows it to fit under the most ergonomically designed handguards and rails on the market.

➲ Keymod Handguard

Your AR-15 handguard has huge implications in terms of how much you enjoy your shooting experience. Our Keymod handguard offers more than just the accuracy enhancements that come with a free-floating rail. It features a full-length picatinny top rail that sits flush with M4 flat top receivers allowing you to have more space for optics and back up iron sights. The slim profile is comfortable to grip while still allowing enough room for low profile gas blacks underneath. This AR-15 handguard is machined from 6061 aluminum, has a hard coat anodized black finish, and the strong attachment of accessories to the Keymod handguard are unaffected by recoil.

➲ Colt Competition Style Barrel

The barrel is one of the few components that directly affect the accuracy and weight of your build.  This barrel has a nitride finish for increased strength and durability. While featuring a special contour that is designed to be lighter than a conventual SOCOM barrel giving you that extra edge when shooting 3-gun competitions. This barrel offers a 1:8 twist rate, suitable for both heavy and light ammunition.  It is corrosion resistant resulting in an extended barrel life that is longer than conventional chrome lining. Thus, being the perfect barrel for long distance shooting, competitions, hunting and practically any shooting application you’ll subject your AR-15 too.

➲ A2 Flash Hider

The muzzle device is designed to perform a specific task, like suppress flash intensity or reduce felt recoil. This A2 Flash Hider is machined from quality steel and finished with an exceptionally corrosion resistant salt bath nitride for a lifetime of service. It provides effective flash suppression that preserves the shooter\\\\\\\\\\\\\\\'s night vision by disrupting the muzzle flash when firing in low lighting conditions. While its closed bottom with top and side ports offers reduced dust signature when shooting from the prone position while additionally acting as a compensator.

CBC provides a wide selections of AR-15 upper assemblies in a variety of styles and lengths - all partial AR-15 uppers are assembled with everything less the charging handle and bolt carrier group. Our partial upper assemblies offer quality and performance that will satisfy the most demanding shooter. Better yet, all CBC AR-15 uppers are custom built-to-order enabling us to provide you with the best prices you will find anywhere. The quality of our AR-15 uppers are backed by our Lifetime Warranty - if any CBC upper assembly becomes defective, we will repair or replace it at no charge. Get your AR-15 upper assembly at CBC today and save with free shipping!

Additional information

Weight 4 lbs
Dimensions 27.5 × 4.5 × 4.5 in


Barrel Material

Barrel Coating

Barrel Length

Twist Rate

Thread Pattern

Gas System Length


Handguard Length


Bolt Carrier Group & Charging Handle

No Bolt Carrier Group & Charging Handle

8 reviews for AR-15 Upper Assembly – 16″/ 5.56 / 1:8 / 12″ CBC Arms Keymod AR-15 Handguard / Rail

  1. Anthony Solesbee

    Bought this CBC upper assembly very last minute and everyone at CBC was so helpful and made sure I received it in time. The upper is absolutely killer looking. Can’t wait to bolt it to my lower!

  2. Allen Ward

    I received my new upper today and the upper is well built and looks fantastic. I mated it up to a spare Stag lower and it locked up tight. I really like the Hera Arm handguard and order another one for one of my other rifles. I will be taking to the range this weekend to dial it in.

  3. Joey Rodriguez

    I received my upper today it was put together well. This is my first purchase with CBC, I will continue to shop here. Very helpful staff when I called with a question about shipping. Thanks CBC

  4. Timmy Boyd

    I am more than pleased with the transaction and the awesome Upper I received from CBC . More than I expected and at a fantastic price. I will definitely be doing all my future AR business here. Thank you CBC .

  5. Drew

    I got this upper in a 1 in 9 twist and it is perfect. The construction is superb and it was shipped very quickly once the barrels came in. Thanks for making this available and for doing a great job helping us make America safe again!
    Looking forward to building another rifle with one of your uppers here soon!

  6. Joe n

    Got the upper in and was amazed on how well the upper was built and the quality of the upper was ,I’m am very pleased with the purchase and will buy from them again plus you can’t beat there customer service there great to deal with.a good friend of mine bought an upper that cost three times as much and he even said the quality of the upper I bought from cbc is better than what he got which pissed him off so now he will be buying from cbc keep up the good work thank you guys very much for the awesome upper and great customer service

  7. Eric Nail

    I’m so impressed with CBC. They’re putting out amazing value parts that make building a high quality rifle possible without breaking the bank. They really are the real deal.

    My upper was shipped fully assembled, drop in ready and quickly! The turn around was much less than 2 weeks, (5-6 days) and they keep you up to date with tracking of course.

    The upper itself is accurate, looks incredible, light weight, and extremely convenient with pretty much every mounting option I could ever want. Did I also say it looks good? Cause it looks so sexy…

    If youMre on the fence, really it’s worth while to take the plunge. I recommend to all my friends and family.

    Eric nail- WA State

  8. Ken

    I have been waiting to make this review until I have put several hundred rounds through this upper. I have now reached the 500 round mark and am ready to review! First off I want to talk about shipping, it was low-cost and fast. It took CBC about 3 days to send it out and about 5 more days for it to reach my front porch, so 8 total.. not bad!!
    Next I will touch on the looks and feel of this upper.. It has no machining marks and looks and feels extremely high quality for the very low price! The black finish is nice and polished and matches my stag arms lower perfectly. (the picture is very accurate of what it looks like)
    The barrel is 5.56, 1/8 twist, 16 inches, which in my opinion is the best twist rate and best length for a 556 barrel.
    Next is the Accuracy.. I took it out and shot at 50 and 100 yards with 50,55,62gr ball ammo and easily got 1/2 inch to 1 inch groups with each different ammo types.
    The upper is very lightweight, looks great, feels great, shoots very well (accurate and 0 malfunctions in 500 rounds)
    It has m4 feed-ramps and is very reliable thus far.
    BEST OF ALL I GOT THIS UPPER FOR $245!! YES $245 !!!!!! That’s half as much as pretty much any Midwest industries upper!!
    I recommend CBC to everyone and I think their quality control and prices are very hard to beat!
    Thank you CBC I will be shopping with you again!

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