Brownells Ar-15 5.56 M4 Barrel Group 14.7'' 1-7 Twist, Carbine Gas

The Brownells AR-15 5.56 M4 barrel group delivers mil-spec performance in a compact 14.7″ package built for carbine-length gas systems. Manufactured to US Government Contractor standards, this barrel assembly arrives pre-assembled with front sight base, gas tube, and handguard cap already installed—meaning you can move straight to fitting it into your upper receiver without hunting down compatibility parts. It's the kind of no-fuss upgrade that saves you time on the bench and gets your rifle running.

Built from 4150 chrome moly steel with a hard chrome-lined bore, this barrel handles the abuse that comes with regular shooting. The 1-7 inch twist rate stabilizes 62-grain rounds and heavier, making it equally at home slinging standard military loads or match-grade ammunition downrange. Every barrel that leaves Brownells undergoes high-pressure testing and magnetic particle inspection—quality assurance that matters when you're relying on your firearm. The chamber is spec'd for 5.56x45mm NATO, and the barrel is clearly marked so you know exactly what you've got.

Whether you're building an M4 clone, assembling a patrol carbine, or refreshing an existing upper, this barrel group cuts out the guesswork. The round handguard cap and proper gas system length are already matched to the barrel, so there's no second-guessing fit or function. It's straightforward, vetted hardware that performs.

Key Features

• 14.7″ barrel length optimized for carbine-length gas systems
• 1-7 twist rate stabilizes 62-grain and heavier ammunition
• 4150 chrome moly steel with hard chrome-lined bore for durability
• F-marked front sight base pre-installed
• Slip ring assembly and round handguard cap included and fitted
• High-pressure tested and magnetic particle inspected
• 5.56x45mm NATO chamber
• Mil-spec construction to US Government Contractor standards

Specifications

Frequently Asked Questions

What ammunition does this barrel stabilize?

The 1-7 twist rate is rated to handle 62-grain rounds and heavier. This makes it suitable for standard military 5.56 loads as well as match-grade and specialty ammunition in that weight range and above.

Is this barrel group ready to install out of the box?

Yes. The front sight base, gas tube assembly, slip ring, and handguard cap come pre-installed and properly fitted. You can install it directly into your upper receiver without sourcing additional parts.

What quality control does this barrel undergo?

Every barrel is high-pressure tested, then inspected using magnetic particle inspection and gauging to verify there are no defects before shipment.

Is this barrel marked with specs?

Yes. The barrel is marked "5.56x45mm NATO MFR 12238 MP HP 1-7" so you can verify caliber, chamber, and twist rate at a glance.