$35.65
Availability: In Stock
The CMMG MK4 AR-15 lower receiver is a precision-forged foundation for building a reliable, accurate rifle from the ground up. Machined from 7075 T6 aluminum and finished in Armor Black Cerakote, this mil-spec lower receiver delivers the durability and dimensional accuracy you need to assemble a quality AR-15 or customize an existing platform. Whether you're a first-time builder looking to put together your own rifle or an experienced gunsmith stocking options for future projects, a stripped lower receiver gives you complete control over the final build and lets you pair it with your choice of lower parts kits and upper assemblies.
CMMG has built a reputation for attention to detail in AR platform manufacturing, and the MK4 lower reflects that standard. The 7075 T6 aluminum forging starts from premium material and is machined to mil-spec tolerances, ensuring reliable function and longevity. The Armor Black Cerakote finish resists corrosion and wear, holding up to regular handling and field use without showing wear as quickly as anodize alone.
This is a stripped lower receiver—it comes without a fire control group, trigger assembly, or stock hardware—so you'll need a mil-spec lower parts kit to complete the build. That flexibility is the whole point: you choose the trigger, safety, buffer system, and controls to match your intended use, whether that's hunting, competition, home defense, or just putting rounds downrange at the range.
| Receiver Type | Stripped Lower Receiver |
| Platform | MK4 AR-15 |
| Material | Forged 7075 T6 Aluminum |
| Finish | Armor Black Cerakote |
| Compatibility | Mil-spec lower parts kits |
A mil-spec lower parts kit, which includes the fire control group, safety selectors, trigger, hammer, and related springs and pins. You'll also need an upper receiver assembly and stock/buffer tube setup to build a complete rifle.
Yes. The CMMG MK4 lower receiver is machined to mil-spec dimensions and will work with any mil-spec AR-15 upper receiver.
The receiver is finished in Armor Black Cerakote, a durable ceramic-based coating that resists corrosion and scratching better than standard anodize.
This is a stripped lower receiver with no serialization restrictions as a component. Consult federal, state, and local laws regarding AR pistols and short-barreled rifles in your jurisdiction before completing your build.
SKU: 120913821 • Width: 6in • Height: 2.4in • Depth: 11in • Weight: 0.71oz
Availability: In Stock
The CMMG MK4 AR-15 lower receiver is a precision-forged foundation for building a reliable, accurate rifle from the ground up. Machined from 7075 T6 aluminum and finished in Armor Black Cerakote, this mil-spec lower receiver delivers the durability and dimensional accuracy you need to assemble a quality AR-15 or customize an existing platform. Whether you're a first-time builder looking to put together your own rifle or an experienced gunsmith stocking options for future projects, a stripped lower receiver gives you complete control over the final build and lets you pair it with your choice of lower parts kits and upper assemblies.
CMMG has built a reputation for attention to detail in AR platform manufacturing, and the MK4 lower reflects that standard. The 7075 T6 aluminum forging starts from premium material and is machined to mil-spec tolerances, ensuring reliable function and longevity. The Armor Black Cerakote finish resists corrosion and wear, holding up to regular handling and field use without showing wear as quickly as anodize alone.
This is a stripped lower receiver—it comes without a fire control group, trigger assembly, or stock hardware—so you'll need a mil-spec lower parts kit to complete the build. That flexibility is the whole point: you choose the trigger, safety, buffer system, and controls to match your intended use, whether that's hunting, competition, home defense, or just putting rounds downrange at the range.
| Receiver Type | Stripped Lower Receiver |
| Platform | MK4 AR-15 |
| Material | Forged 7075 T6 Aluminum |
| Finish | Armor Black Cerakote |
| Compatibility | Mil-spec lower parts kits |
A mil-spec lower parts kit, which includes the fire control group, safety selectors, trigger, hammer, and related springs and pins. You'll also need an upper receiver assembly and stock/buffer tube setup to build a complete rifle.
Yes. The CMMG MK4 lower receiver is machined to mil-spec dimensions and will work with any mil-spec AR-15 upper receiver.
The receiver is finished in Armor Black Cerakote, a durable ceramic-based coating that resists corrosion and scratching better than standard anodize.
This is a stripped lower receiver with no serialization restrictions as a component. Consult federal, state, and local laws regarding AR pistols and short-barreled rifles in your jurisdiction before completing your build.
SKU: 120913821 • Width: 6in • Height: 2.4in • Depth: 11in • Weight: 0.71oz