Green Mountain 5.56 AR-15 Barrel 16" M4 Phosphate - GM-M9
$182.95
Only 3 left in stock
Upgrade your AR-15 build with the Green Mountain 5.56 AR-15 Barrel 16″ M4 Phosphate, a precision-engineered component designed for reliable performance in tactical and recreational shooting applications. Manufactured to exacting standards, this carbine-length barrel delivers consistent accuracy and durability for 5.56 NATO platforms.
Key Features
- Chrome-lined bore and chamber with phosphate exterior finish for superior corrosion resistance and extended service life
- M4 profile barrel balances weight and rigidity for improved handling during rapid fire sequences
- Carbine-length gas system ensures smooth cycling with standard AR-15 components
- 1:12 twist rate optimized for a range of bullet weights in 5.56 NATO ammunition
- 0.75″ gas block journal and 1/2×28 muzzle threads for versatile accessory mounting
Technical Specifications
- Barrel Length: 16 inches
- Platform: AR-15 / M4 compatible
- Cartridge: 5.56 NATO
- Finish: Phosphate + Chrome Lined
- Profile: M4
- Gas System: Carbine
- Gas Block Journal: 0.75 inches
- Twist Rate: 1:12
- Muzzle Thread: 1/2×28
- Weight: 30.8 oz
Why Choose This Barrel
This Green Mountain barrel addresses common shooter concerns by providing a chrome-lined interior that resists fouling and wear, allowing for higher round counts without performance degradation. The M4 profile reduces overall weight compared to heavier contours while maintaining structural integrity for sustained use. Its standard carbine gas system and thread pattern simplify integration into existing builds, minimizing the need for custom parts or adjustments.
Ideal for builders seeking a dependable, mil-spec style barrel that prioritizes longevity and compatibility over specialized match-grade features.
Installation and Compatibility Notes
Designed for standard AR-15 upper receivers with M4 feed ramps. Professional installation is recommended to ensure proper headspacing and alignment. This barrel is compatible with most aftermarket gas blocks, muzzle devices, and handguards featuring carbine-length gas systems.
Enhance your firearm’s reliability and accuracy—select the Green Mountain 5.56 AR-15 Barrel for your next build or upgrade.
| Weight | 30.8 oz |
|---|---|
| Dimensions | 16 in |
| Finish | Phosphate + Chrome Lined |
| Barrel Profile | M4 |
| Cartridge Compatibility | 5.56 NATO |
| Gas Block Journal | 0.75 |
| Barrel Length | 16" |
| Gas System Length | Carbine |
| Platform | AR-15 |
| Twist Rate | 1:09 |
| Muzzle Thread Pattern | 1/2×28 |
| MPN | GM-M9 |
| UPC | 33762 |
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.
