Green Mountain 5.56 AR-15 Barrel 20" M16 A1 Phosphate - GM-M14
$194.95
Out of stock
Discover the precision and reliability of the Green Mountain 5.56 AR-15 Barrel 20″ M16 A1 Phosphate, a premium choice for builders seeking authentic M16A1-style performance in their AR-15 platform. This 20-inch barrel combines a lightweight pencil profile with proven military specifications to deliver exceptional accuracy and durability for tactical, competitive, or retro builds.
Key Features and Benefits
- Chrome-Lined Bore and Chamber: Enhances barrel longevity by resisting wear from high-volume shooting while providing superior corrosion resistance and easier cleaning.
- Phosphate Finish: Offers a non-reflective, matte black coating that protects against environmental elements and maintains a low-profile appearance suitable for field use.
- M16 A1 Pencil Profile: Reduces overall weight for improved handling and maneuverability without sacrificing the structural integrity needed for reliable operation.
- Rifle-Length Gas System: Ensures smooth, consistent cycling with 5.56 NATO ammunition, minimizing recoil and promoting reliable function across a wide range of loads.
- 1:12 Twist Rate: Optimized for stabilizing heavier bullets, making it ideal for precision shooting and compatibility with both .223 Remington and 5.56 NATO cartridges.
Technical Specifications
- Platform: AR-15
- Caliber: 5.56 NATO
- Barrel Length: 20 inches
- Barrel Profile: Government / M16 A1 Pencil
- Gas System: Rifle length with 0.625″ gas block journal
- Twist Rate: 1:12
- Muzzle Thread: 1/2×28
- Finish: Phosphate with chrome-lined bore and chamber
- Steel: 41V50 alloy
- Weight: Approximately 34.8 oz
Why Choose This Green Mountain Barrel?
Engineered for enthusiasts who demand mil-spec quality, this barrel addresses common challenges like premature wear, inconsistent gas operation, and excessive weight in longer barrels. The combination of chrome lining and phosphate coating ensures it withstands demanding conditions while delivering consistent accuracy. Its classic M16 A1 design makes it a perfect fit for retro AR builds or modern tactical setups requiring proven reliability.
Whether you’re upgrading an existing rifle or starting a new project, this barrel provides the foundation for a dependable, high-performing firearm.
| Weight | 34.8 oz |
|---|---|
| Dimensions | 20 in |
| Finish | Phosphate + Chrome Lined |
| Barrel Profile | Government / SOCOM |
| Cartridge Compatibility | 5.56 NATO |
| Gas Block Journal | 0.625 |
| Barrel Length | 20 |
| Gas System Length | Rifle |
| Platform | AR-15 |
| Twist Rate | 1:12 |
| Muzzle Thread Pattern | 1/2×28 |
| MPN | GM-M14 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
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