Product Description The Rosco Manufacturing Purebred 10.5" 300 Blackout Barrel is a precision-engineered rifle barrel purpose-built for Short Barreled Rifle (SBR) and pistol configurations, with optimized compatibility for suppressor use. Constructed from high-quality stainless steel and finished in a durable Nickel Boron coating, this barrel offers superior corrosion resistance and a smooth, low-friction surface that promotes reliable cycling. It was engineered as a direct precision replacement for MK 18 platforms originally chambered in 5.56 NATO, allowing seamless caliber conversion without sacrificing fit or function. The 10.5" length is also an ideal choice for carbine builds that require additional rail space to comfortably mount aiming devices such as the PEQ-15, D-BAL series lasers, or other laser aiming systems. With a 1:7" twist rate and a 5/8"x24 threaded muzzle, this barrel is fully ready for suppressor attachment straight out of the box. Product Highlights Suppressor-Ready Design: Threaded 5/8"x24 muzzle pattern allows direct attachment of suppressors and muzzle devices without additional adapters. MK 18 Drop-In Replacement: Engineered as a direct precision replacement for MK 18 platforms chambered in 5.56 NATO, enabling a straightforward 300 Blackout conversion. Nickel Boron Finish: The Nickel Boron coating provides excellent corrosion resistance, enhanced lubricity, and a hard, durable surface for long-term performance. Optimized for Laser Aiming Devices: The 10.5" barrel length provides adequate rail space for PEQ-15s, D-BAL series, and other laser aiming devices to be mounted comfortably. Stainless Steel Construction with 1:7" Twist: Precision stainless steel barrel with a 1:7" twist rate stabilizes a wide range of 300 Blackout projectile weights for consistent accuracy. Specs Brand: Rosco Manufacturing Model: Purebred MPN: PB-105-HB-300BLK-7-P UPC: 181969500289 Caliber: 300 Blackout Length: 10.50" Material: Stainless Steel Finish: Nickel Boron Thread Pattern: 5/8"x24 Twist Rate: 1:7" Weight: 21.09 oz Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer. ]]>