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CMMG AR-15 MK4 T Complete Upper Receiver .300 AAC Blackout 16" Barrel RKM11 KeyMod Hand Guard A2 Muzzle Brake Matte Black 30B129A

CMMG, Inc.
Ships from Warehouse 7
Typically ships within 1 to 2 business days.
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CMMG is a leading manufacturer of AR-15 and AR-15 related accessories. CMMG's commitment to quality and creating product at the best value at the best price is unmatched. This complete upper receiver is designed to connect seamlessly with your existing AR-15 or AR-15 pattern lower receiver. For your convenience, a bolt carrier group is included and everything on this complete unit features a matte black finish.

Specifications and Features:
CMMG Complete Upper Receiver 30B129A
.300 AAC Blackout
16" 4140 Chrome-Moly steel medium taper profile
Threaded 5/8x24
RKM11 KeyMod hand guard
Forged 7075-T6 Aluminum M4 Type Upper
CMMG A2 Compensator
Bolt carrier group
Charging Handle
Matte black


Item#: ARR-118-035,7-30B129A,3-0410031,2-CMMG30B129A
Total number of Reviews: 1

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5.0 5
"I love this upper. I took it to the range today for the first time to sight in with iron sights. It cycles great on my standard mil-spec lower (carbine buffer). My shots were perfect circles (no key-holing) at 10 yd, 25 yd, and 50 yd. I was shooting 220 gr. subsonic Remington ammo. The only thing I might change is I might buy a better bolt carrier group (nickel boron or EXO coated), but the BCG that comes with this upper is as good as any standard mil-spec BCG. Very pleased with this purchase!"