Proof Steel Drop in Barrel for Pistol Gas System AR-15 Compatible Firearms 300 BLK 12.5" 1:7 Twist 5/8-24

The Proof Steel Drop in Barrel for Pistol Gas System AR-15 Compatible Firearms in 300 BLK with a 12.5" length is designed for operators using short-stroke, pistol-length gas systems in modern AR platforms. This barrel is suitable for tactical professionals, law enforcement specialists, and serious civilian shooters who prioritize reliability in compact, high-performance builds.

Manufactured by Proof Research Inc., this steel barrel features a 1:7 twist rate optimized for stabilizing 110–220 grain projectiles commonly used with 300 BLK ammunition. The 5/8-24 threaded muzzle is compatible with industry-standard suppressors, compensators, and flash hiders, allowing for versatile use without the need for additional adapters. The drop-in design simplifies installation, enabling users to replace the original barrel assembly with minimal tools.

This barrel is ideal for those looking to enhance their AR-15 platform's performance, particularly in applications requiring adaptability across various mission profiles. Its steel construction provides durability and heat dissipation during extended use, making it a reliable choice for both duty applications and training cycles.