Colt 11.5 inch M4 Commando Upper Receiver Assembly

(46 reviews)
Current Stock:

The Colt LE6933CK Upper Assembly is used on the R0933 Commando model rifle. This upper receiver allows for a free-floated barrel and also features a gas-block mounted fixed front sight post with bayonet lug and a backup rear sight. The barrel is Colt's standard 11.5" chrome lined M4 barrel with an A2 flash hider up front.

Package Contents

  • Colt LE6933CK Complete Upper Assembly
  • Complete M4 Full Auto Bolt Carrier Assembly
  • Charging Handle
  • Backup rear sight
  • Manual


  • 11.5-Inch 1/7 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 5.56mm ammunition, including the NATO M855/SS109 and U.S. M193, utilizing a rifling twist of 1 turn in 7"
  • 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 - 5.56mm
  • Gas Direct system, Locking bolt
  • Front Sight - Adjustable front
  • Rear Sight - Target sight adjustable for windage and elevation
  • Flash Hider


  • 5
    Colt M16 10.5" upper complete

    Posted by Peter on 1st Sep 2022

    Great product, great service. Got here to my door perfectly. Would recommend to my friends

  • 4
    Colt 11.5 inch M4 Commando Upper Receiver Assembly

    Posted by Unknown on 29th Jul 2022

    The Colt 11.5 full upper was shipped in a full Colt Carbine CR6933 box with no padding. Upon receipt the front post sight had penetrated the box and was sticking out. No damage and there was a outer plastic bag to prevent oil staining which USPS doesn’t like to see. All in all I was quite pleased with the product and would recommend. More detail to packaging for shipment would be appreciated.

  • 5
    Outstanding quality!

    Posted by Dan Curtis on 27th Nov 2021

    This product was outstanding! The accuracy out of the box was amazing.

  • 5
    This is a proven classic

    Posted by 18echo on 15th Oct 2021

    I know it’s been in use for only for aprox 26 years , but the moment it came into service was a instant favorite for a chosen and lucky few , this modern 9633 is solid in all sense of the word . I’m glad I found one available in A.U.

  • 5

    Posted by Ross on 12th Oct 2021

    What can I say, it’s a commando upper . It’s bad ass. And arms unlimited is always fast and excellent. 10/10 would buy again

  • 5
    Colt 6933$ Complete Upper

    Posted by Douglas Pearsall on 7th Sep 2020

    Best place in the US for Colt uppers.

  • 5
    Genuine Colt Quality.

    Posted by Jerry on 6th Sep 2020

    Couldnt ask for better than this for a great SBR or pistol build. Genuine Colt from end to end. Fast shipping at an excellent price considering these parts seem to be harder and harder to find. Big Shout out to AU. thanks guys

  • 5
    Colt 11.5 inch M4 Commando Upper Receiver Assembly

    Posted by Richard on 31st Aug 2020

    Easy purchase, fast shipping, very satisfied..........

  • 5
    Colt original manufactured product

    Posted by Jack on 28th Apr 2020

    Military/Police issue brand new for S.B.R. In original Colt shipping box and sealed plastic bag and coating. Super service, great prices and good shipping.