I have been on the fence for a while trying to decide what 9mm ar15 UPPER RECIEVER ASSEMBLY to purchase as part of our 9mm ar15 project. I chose the CMMG for four reasons. The first two reasons being I could use it with my HAHN PRECISION 9mm RECEIVER BLOCK with COLT 9mm 32 ROUND MAGAZINES. The third reason is the CMMG 9mm AR15 UPPER RECIEVER ASSEMBLY utilizes a bolt carrier group modified to accept any AR15 trigger group as opposed to the competition that relies on a dedicated 9mm hammer to function correctly. The fourth an final reason is that BROWNELLS has the unit in stock.
I will be throwing out the A2 handguard in favor of a MAGPUL FOLIAGE GREEN MOE CARBINE HANDGUARD. The FLASH HIDER will be replaced with a YANKEE HILL MACHINE YHM-9853-36-A PHANTOM FLASH HIDER for a WRAITH XL QD SOUND SUPPRESSOR with a 1/2″-36 thread.
There will be updated pictures on the 9mm ar15 PROJECT page.
This complete CMMG AR-15 M4 LE Upper Assembly features a chrome-moly steel barrel with a WASP Melonite treated bore and exterior. The upper makes use of a ramped, 9mm specific bolt that enables the use of a standard AR-15 hammer (dedicated 9mm hammers are not compatible), and comes complete with a shortened ejection port/ejection port cover and large polymer brass deflector. Upper must be installed on a lower receiver compatible with, or modified to accept, Colt-Style 9mm Luger box magazines.
CMMG’s durable Weapons Armament Surface Protection (WASP) Melonite treatment is a unique protective coating applied to the barrel that surface-hardens the metal, extending barrel service life by reducing friction in the bore and lessening bore surface wear. Also referred to as Nitriding, this treatment produces an extremely hard, slick surface on steel that resists carbon adhesion and increases corrosion resistance, making for easier cleaning and maintenance. Nitriding converts the steel’s surface without any build-up, retaining all the benefits of traditional chrome lining without suffering from the accuracy degradation commonly encountered due to uneven application of chrome inside the barrel’s bore.
- Upper Receiver: A3 Flat-Top
- Barrel Length: 16″
- Barrel Contour: M4
- Barrel Material: Chrome Moly Steel
- Muzzle Thread Pattern: 1/2″-36
- Chrome Lined: No
- Barrel Finish: WASP Melonite
- Twist Rate: 1 in 10″
- Chamber: 9mm Luger
- Muzzle Device: A2 Flash Hider
- Gas System Length: None, Blowback
- Handguard: Polymer M4 -Style, Carbine Length
- Sights: Mil Spec A2 “F” Marked Front, No Rear
- Compatible with Colt-Style 9mm Luger Box Magazines, Not Included
- Lower Receiver will Require a 9mm Luger Magazine Well Adapter Block for use, Not Included
- Ramped 9mm Bolt Allows use of Standard AR-15 Hammer, Dedicated 9mm Hammer NOT Needed or Compatible