Green Mountain 5.56 AR-15 Barrel 16" M4 Fluted Phosphate - GM-M6
$206.95
Only 2 left in stock
Enhance the performance and reliability of your AR-15 build with the Green Mountain 5.56 AR-15 Barrel 16″ M4 Fluted Phosphate. Precision-engineered for tactical and recreational shooters, this carbine-length barrel delivers exceptional accuracy, durability, and lightweight handling in a versatile 16-inch package.
Key Features
- Straight fluted profile reduces overall weight without compromising structural integrity, making it ideal for extended range sessions or dynamic shooting scenarios.
- Chrome-lined bore and chamber paired with a phosphate exterior finish provides superior corrosion resistance and simplifies cleaning while extending barrel life.
- 1:9 twist rate stabilizes a wide range of 5.56 NATO and .223 Remington ammunition for consistent groupings across various bullet weights.
- Carbine-length gas system with a 0.75″ gas block journal ensures reliable cycling and smooth operation in standard AR-15 platforms.
- 1/2×28 muzzle thread pattern allows easy attachment of suppressors, flash hiders, or compensators for customization.
Specifications
- Barrel Length: 16 inches
- Cartridge Compatibility: 5.56 NATO
- Platform: AR-15
- Finish: Phosphate with chrome-lined bore and chamber
- Barrel Profile: Straight fluted M4
- Gas System: Carbine
- Gas Block Journal: 0.75 inches
- Twist Rate: 1:9
- Muzzle Thread: 1/2×28
- Weight: 29.6 ounces
Why Choose This Product
Built to military-inspired standards, this barrel addresses common shooter pain points like excessive weight, fouling, and inconsistent accuracy. The fluted design lightens your rifle for better maneuverability, while the chrome lining protects against wear from high-volume fire. Whether you’re building a home-defense carbine or a competition-ready setup, it offers dependable performance backed by Green Mountain’s reputation for quality rifle barrels.
Upgrade your AR-15 with this precision-engineered barrel to achieve optimal balance, accuracy, and longevity in your firearm.
| Weight | 29.6 oz |
|---|---|
| Dimensions | 16 in |
| Finish | Phosphate + Chrome Lined |
| Barrel Profile | Straight Fluted |
| Cartridge Compatibility | 5.56 NATO |
| Gas Block Journal | 0.75 |
| Barrel Length | 16" |
| Gas System Length | Carbine |
| Platform | AR-15 |
| Twist Rate | 1:9 |
| Muzzle Thread Pattern | 1/2×28 |
| MPN | GM-M6 |
| UPC | 33760 |
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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