CMMG Mk3 .308 Win / LR-308 Complete Lower Receiver Parts Kit - Black - 38CA6DC
Product Description
Assembling a large-frame modern sporting rifle or configuring an heavy-hitting .308 Winchester project introduces an immediate mechanical and dimensional bottleneck: standard AR-15 parts incompatibility. While small-frame AR components share unified blueprints, large-frame receivers change scale drastically across pivot pin lengths, bolt catch profiles, and takedown dimensions. Forcing standard mil-spec parts into a larger receiver block leads to loose play, geometry skips, or failure to lock open. The **CMMG® Mk3 .308 AR Complete Lower Receiver Parts Kit (38CA6DC)** completely eliminates these multi-platform pairing liabilities, packaging an original equipment manufacturer (OEM) kit explicitly scaled to the DPMS LR-308 profile.
Precision-manufactured within CMMG’s advanced domestic facilities to meet unyielding structural specifications, this complete lower parts kit provides a rock-solid, match-grade foundation. Unlike generic hardware bags that leave you digging through loose parts, CMMG separates components into five distinct, color-coded pouches to streamline workbench tracking. Every critical pin, safety detent, and catch arm is stamped from high-tensile, heat-treated carbon structural steel and treated with a rich, uniform black manganese phosphate or black oxide jacket. This advanced armor shrugs off aggressive field moisture, corrosive unburnt powder scale, and harsh bench solvents.
In high-velocity tactical indexing, routine long-range hunts, or intensive firing cycles, the absolute cyclic timing of your platform relies on the consistency of its trigger group. The 38CA6DC package ships fully loaded with a conventional single-stage **Mil-Spec trigger and hammer configuration**, calibrated to deliver a highly predictable 6.0 to 6.5-pound service rifle breakdown. Outfitted with an authentic, texturized matte black A2 polymer pistol grip, an specialized threaded screw-in bolt catch pin, and expanded .308-specific takedown hardware, this comprehensive bundle eliminates tolerance stack errors to finish your custom receiver build with total mechanical authority.
*Armorer Bench Notes & Technical Assembly Guidance: The CMMG Mk3 kit features full native cross-compatibility with **CMMG Mk3 lowers, Aero Precision M5 frames, and standard DPMS LR-308 pattern receivers**. CRITICAL COMPATIBILITY NOTE: This unibody framework is explicitly structured for the LR-308 platform and will physically fail to fit proprietary Armalite AR-10 or Rock River Arms frames due to different pivot pin configurations and receiver heights. When beginning installation on your workbench, note that the bolt catch utilizes a specialized threaded screw-in pin rather than a traditional roll pin; use a precision hex driver to tighten it down securely. Apply a single drop of premium synthetic gun oil to each detent well and spring coil during installation to ensure silky-smooth safety selector toggling and clean, repeatable magazine release tracking right out of the gate.
Key Features
- Color-Coded Pouch System: Components are neatly separated into five colored bags (Clear, Yellow, Red, Blue, Green) to simplify parts inventory tracking and eliminate assembly confusion.
- Large-Frame .308 Optimization: Packed with native .308-specific receiver pivot pins, takedown pins, and custom bolt catch components to prevent large-frame geometry errors.
- Threaded Bolt Catch Interface: Trades archaic roll pins for a streamlined, high-strength threaded bolt catch screw-in pin, cutting down the risk of hammer marring on your receiver walls.
- Complete Mil-Spec Trigger Included: Outfitted with a complete single-stage fire control group featuring crisp, case-hardened sears to ensure a reliable 6.5 lb trigger break line.
- Traditional A2 Grip Architecture: Includes a high-impact textured black polymer A2 pistol grip, complete with its original structural lock washer and grip retention bolt.
Product Specifications
- Brand: CMMG
- Model Line: Mk3 Series Lower Receiver Performance Upgrades
- MPN/SKU: 38CA6DC (Also tracked as CMMG38CA6DC)
- UPC Code Profile: 852005002097
- Firearm Platform Focus: CMMG Mk3 / DPMS LR-308 (Large Frame Architecture)
- Caliber Versatility Matrix: .308 Winchester, 7.62x51mm NATO, 6.5 Creedmoor, .243 Win
- Component Core Material: Heat-Treated Carbon Structural Steel / Performance Alloys
- Exterior Finish Treatment: Non-Reflective Manganese Phosphate / Matte Black Oxide Armor
- Pistol Grip Composition: Injection-Molded High-Density Matte Black Polymer (A2 Style)
- Fire Control Group Profile: Mil-Spec Conventional Single-Stage Trigger Group (6.0 - 6.5 lbs Pull)
- Packaging Arrangement: 5-Tier Labeled Color-Coded Modular Pouches
- Included Take-down Parts (Clear Bag): 308 Takedown Pin, 308 Pivot Pin, 2x Detents, 2x Detent Springs
- Included Catch Hardware (Yellow Bag): Bolt Catch, Plunger, Spring, Screw-In Threaded Pin, Buffer Retainer & Spring
- Included Fire Control Parts (Red Bag): Hammer, Trigger, Disconnector, 2x Retaining Pins, 3x Tailored Springs
- Included Magazine Components (Blue Bag): Magazine Catch, Magazine Catch Spring, Aluminum Release Button
- Included Selector Hardware (Green Bag): Safety Selector Lever, Detent, Spring, Grip Screw & Washer
- Country of Manufacture: United States of America
