Colt AR15/SMG 9mm Upper Receiver Assembly | 16" Barrel

$700.00 $599.00
(7 reviews)
Current Stock:

The Colt AR6951CK Upper Assembly is utilized on the semi-automatic version of the SMG model submachine gun. This upper receiver allows for a free-floated barrel and also features a gas-block mounted fixed front sight post with bayonet lug. The barrel is Colt's standard 19" chrome lined M4 barrel with an A2 flash hider up front.

Package Contents

  • Colt AR6951CK Complete Upper Assembly
  • Complete 9mm SMG Full Auto Bolt Carrier Assembly
  • Charging Handle


  • 16-Inch 1/10 RH twist Mil-Spec chrome lined MP tested barrel
  • Unique direct gas operating system eliminates the conventional operating rod and results in fewer and lighter components
  • Accommodates the full range of 9mm NATO ammunition
  • Straight-line construction disperses recoil straight back to the shoulder, increasing handling capabilities, especially during repeated fire
  • Cartridge case deflector allows easy operation in both right and left handed shooting positions for increased tactical applications
  • Muzzle compensator further reduces muzzle climb and helps eliminate flash and dust signatures
  • Ejection port cover protects the chamber from dust and mud
  • Field strips easily without special tools for simple field user maintenance
  • Flat top receiver allows for removable carrying handle and easy mounting of accessories
  • High strength materials for greater comfort and effectiveness
  • Caliber - 9mm
  • Closed Bolt, Blowback
  • Front Sight - Adjustable front
  • Flash Hider


  • 5
    Colt Fast Shipping

    Posted by JoeyP on 10th Feb 2024

    Cage marked upper. CMP marked barrel. FAST shipping.

  • 5
    Colt AR upper

    Posted by Luis Barrera on 9th May 2023

    Excellent product quality & first rate service. I will definetly purchase again from arms unlimited !

  • 5
    Colt’s still the best

    Posted by Yukon58 on 1st May 2023

    I decided to go with this 16” upper for my Colt lower after the fiasco with the atf pistol brace ruling. I wasn’t going to fluff around so I went all Colt and am glad I did. The BCG is superb and it cycles flawlessly with just about any round you feed it. It was the right choice. Teamed with Daniel Defense hardware, this is a great looking, functional CQB PDR at only 31.5” (retracted) & 35” extended.

  • 5
    Excellent upper at a great price!!!

    Posted by Unknown on 5th Sep 2019

    I looked everywhere for a Colt 9mm Upper for a new build and Arms Unlimited had the best price,$100 less than the nearest competitor!!! Also super fast shipping!!!

  • 3

    Posted by Stephen Durst on 18th Jun 2019

    Package was beat up tear in the box, no padding to protect the Upper Receiver. Never received a Colt upper from any vendor that looked like this.

  • 5
    Colt 9mm upper

    Posted by Jeff Armstrong on 1st May 2019

    Excellent price on a quality item look forward to ordering more items from this company

  • 5
    9MM upper

    Posted by Bob on 10th Oct 2018

    Smooth , easy transaction. Probably won`t be my last with Arms Unlimited.