16'' S2W Carbine Length 300 Blk Barrel 1-8 Twist

The Daniel Defense 16" S2W Carbine Length 300 Blk Barrel with 1-8 Twist is a precision-built barrel for shooters who want serious performance in the potent 300 Blackout cartridge. This is a genuine DD component, not a generic off-the-shelf part—built to the same exacting standards as their complete rifles. The 300 Blackout demands a barrel that handles both subsonic and supersonic loads reliably, and this one delivers the rigidity and strength to do it right.

Cold hammer-forged from chromium-molybdenum-vanadium steel, this barrel starts with the good stuff. The metal goes through magnetic particle inspection (MPI) to catch any internal flaws before it ever ships. A manganese phosphate finish protects against wear and corrosion during field use and storage. The M4-type feed ramps ensure smooth chambering across quality ammunition. At the gas block, the barrel measures .750" OD—a heavier, purpose-built profile that tapers toward the muzzle, giving you the rigidity you need for accuracy without unnecessary weight up front.

The 1-8 twist rate is the sweet spot for 300 Blackout, stabilizing both subsonic rounds (220-240 grains) and faster loads (110-125 grains) effectively. Whether you're building a quiet suppressed rifle for hunting or a hard-hitting supersonic upper, this barrel will handle the job. At 16 inches, it's carbine-length, keeping sight radius and handling snappy while preserving as much velocity as the caliber allows. This is a drop-in component for AR-15 builds—just the barrel, ready for your upper receiver assembly.

Key Features

• Cold hammer-forged chromium-molybdenum-vanadium steel construction for strength and accuracy
• Magnetic particle inspected (MPI) to detect internal flaws
• Manganese phosphate finish for corrosion and wear resistance
• M4-type feed ramps for reliable feeding
• S2W (Strength 2 Weight) profile: heavier for rigidity, tapered to reduce muzzle weight
• 1-8 twist optimized for 300 Blackout subsonic and supersonic rounds
• .750" OD at gas block
• 16" carbine-length for balanced handling and velocity

Specifications

Frequently Asked Questions

What is the 1-8 twist rate best for in 300 Blackout?

The 1-8 twist is ideal for 300 Blackout because it stabilizes a wide range of bullet weights. It handles subsonic loads (typically 220–240 grain) used in suppressed builds and works well with supersonic rounds (110–125 grain) for higher-velocity hunting and target work.

Will this barrel work with my AR-15 upper receiver?

Yes, this is a standard AR-15 component barrel with M4-type feed ramps and a .750" OD at the gas block, designed to fit into a 300 Blackout-compatible upper receiver assembly. Your upper must be properly spec'd for the 300 Blackout cartridge.

What does the S2W profile mean?

S2W stands for Strength 2 Weight. It's a heavier, more rigid profile that tapers down toward the muzzle, giving you the structural integrity of a match-grade barrel while keeping unnecessary weight off the front of your rifle.

Is this a complete barrel or just the tube?

This is the barrel itself—the tube. You'll need to pair it with your choice of upper receiver, bolt carrier group, gas tube, and other components to build a complete upper assembly.