CMMG MK/4 AR-15 Upper Receiver Assembly Armor Black
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CMMG
Overview
The CMMG MK/4 AR-15 Upper Receiver Assembly is a stripped upper designed specifically for the AR-15 platform, allowing builders the flexibility to customize their setup according to their preferences. Finished in a sleek black color, this upper receiver provides a solid foundation for your build, ensuring compatibility with a variety of components. It's commonly found in builds featuring a carbine gas system and chambered for .308 Win, making it a versatile choice for those looking to enhance their firearm's performance.
Specifications
August 2026 on GunPartPicker
CMMG MK/4 AR-15 Upper Receiver Assembly Armor Black ranked #109 of the 690 upper receivers builders added on GunPartPicker in August 2026. Builders have been adding it to their builds on GunPartPicker since January 2026. All time, it ranks #93 of the 1,636 upper receivers builders have added. Builds with this upper receiver are nearly all chambered in 5.56 NATO, nearly all on carbine-length gas, and nearly all AR-15.
It was hard to find in August 2026, in stock on only 9 of the 16 days we checked, and today only Optics Planet has it in stock. It dipped to $130.55 at BattleHawk Armory for a stretch in August 2026, under its usual $139.79 to $144.79, so sales do come around. Buying today, the lowest price is $139.79 at Optics Planet, above August's low of $130.55, so a better deal may come back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 35 retailers
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Frequently Built With
The part most often added in each category by the 18 builds that include this one
Bravo Company Manufacturing 16" SS410 5.56 NATO 1:8 Mid-Length AR-15 Barrel - IonBonded Black
WMD Guns AR-15 Gas Tube Nitromet Mid-Length
Magpul MOE M-LOK Handguard, Rilfe, Gray
Wilson Combat Extended AR-15 Charging Handle Latch - TR-CHR
AR-15 Kp-15 Complete Lower Receivers Mil-Spec Polymer - AR-15 Kp-15 Complete Lower Receiver Mil-Spec Polymer Black
Battle Arms AR-15 Bolt Carrier Group - BADBCGM16TI
Builds Featuring This Part
See all 3 →Builds in the community that include the CMMG MK/4 AR-15 Upper Receiver Assembly Armor Black
| Build | Parts | Total |
|---|---|---|
 | 20 | $802.16 |
 | 24 | $6463.66 |
 | 27 | $6944.32 |
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