Green Mountain 5.56 AR-15 Barrel 10.3" M4 Phosphate - GM-M50
$182.95
Only 1 left in stock
Build a reliable and maneuverable AR-15 platform with the Green Mountain 5.56 AR-15 Barrel in a compact 10.3-inch M4 profile. Designed for tactical applications where quick handling and consistent performance matter most, this barrel delivers precision and durability in a lightweight package that enhances overall firearm responsiveness.
Key Features
- Chrome-lined bore and chamber – Resists wear from high-volume shooting and simplifies cleaning while maintaining accuracy over thousands of rounds.
- Phosphate exterior finish – Provides superior corrosion resistance and a non-reflective matte surface ideal for tactical environments.
- M4 profile with carbine-length gas system – Balances weight and strength for improved handling without sacrificing reliability in short-barreled configurations.
- 1:7 twist rate – Stabilizes a wide range of 5.56 NATO ammunition, including heavier projectiles for enhanced terminal performance.
- 0.75-inch gas block journal and 1/2×28 muzzle threads – Offers compatibility with standard gas blocks and popular muzzle devices for easy customization.
Technical Specifications
- Barrel Length: 10.3 inches
- Caliber: 5.56 NATO
- Twist Rate: 1:7
- Finish: Phosphate with chrome-lined bore and chamber
- Profile: M4
- Gas System: Carbine length
- Gas Block Journal: 0.75 inches
- Muzzle Thread: 1/2×28
- Platform: AR-15
- Weight: 22 oz
Why Choose This Barrel
This Green Mountain barrel addresses common pain points for AR-15 builders seeking compact options: excessive weight that slows target acquisition, poor corrosion protection in demanding conditions, and limited bullet stabilization. The combination of military-inspired M4 contouring, proven chrome lining, and precise 1:7 rifling ensures smooth cycling and consistent groupings whether used in home defense setups or range training. Its carbine gas system promotes reliable function even with varied ammunition loads.
Upgrade your AR-15 build today with this high-quality, American-made barrel engineered for performance and longevity.
| Weight | 22 oz |
|---|---|
| Dimensions | 10.3 in |
| Finish | Phosphate + Chrome Lined |
| Barrel Profile | M4 |
| Cartridge Compatibility | 5.56 NATO |
| Gas Block Journal | 0.75 |
| Barrel Length | 10.3 |
| Gas System Length | Carbine |
| Platform | AR-15 |
| Twist Rate | 1:7 |
| Muzzle Thread Pattern | 1/2×28 |
| MPN | GM-M50 |
| UPC | 33748 |
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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