CMMG 16.1" 350 Legend SBN Barrel - Precision Rifle Upgrade

Building a 350 Legend AR-15? The CMMG 16.1" 350 Legend SBN Barrel gives you a factory-headspaced, ready-to-run barrel engineered specifically for Winchester's efficient cartridge. CMMG machines each barrel from 4140 chrome-moly steel and applies a salt-bath nitride finish—a proven combination that resists corrosion and handles the pressures of 350 Legend reliably. At 16.1 inches with a medium-contour profile, it strikes a practical balance between velocity, handling, and sight radius for hunters and precision shooters building a compact, versatile rifle.

The barrel ships threaded 1/2-28 TPI, so it accepts standard suppressors and muzzle devices without additional work. The 0.750-inch gas-block journal accommodates carbine-length gas systems—a familiar setup for anyone comfortable with AR platforms. The 1:16-inch twist rate is optimized for the 350 Legend's bullet weights, and the M4-style extension integrates with any mil-spec bolt carrier. Since CMMG headspaces the barrel at the factory, you skip that step and move straight to assembly.

Whether you're an AR builder looking to chamber a new cartridge or a hunter wanting a legal, efficient option for mid-range game, this barrel delivers straightforward quality without gimmicks. It's the kind of component that earns trust through specs and fit—no hype required.

Key Features

• 4140 chrome-moly steel with salt-bath nitride finish for durability and corrosion resistance
• 16.1-inch barrel length optimized for 350 Legend ballistics
• Medium-contour profile balances weight and rigidity
• 1/2-28 TPI threading accepts standard suppressors and muzzle devices
• Carbine-length gas system compatible with 0.750-inch gas-block journal
• 1:16-inch twist rate tailored for 350 Legend ammunition
• M4-style barrel extension for mil-spec compatibility
• Factory-headspaced—ready for immediate assembly

Specifications

Frequently Asked Questions

Will this barrel work with my mil-spec AR-15 lower?

Yes. The M4-style barrel extension and 0.750-inch gas-block journal are standard AR-15 specifications. It pairs with any carbine-length gas system and mil-spec bolt carrier group.

Can I use a suppressor with this barrel?

Yes. The barrel is threaded 1/2-28 TPI, which is the standard suppressor mount for AR platforms and accepts virtually all 1/2-28 muzzle devices and suppressors on the market.

Is the barrel headspaced when I receive it?

Yes. CMMG headspaces each barrel at the factory, so you can assemble your rifle without needing headspace gauges or a gunsmith.

What gas system length should I use?

This barrel is configured for a carbine-length gas system, which is the most common setup for 16-inch AR builds.