Rosco Mfg Bl-075-Hb-300Blk-5-P Bloodline 300 Out 7.50" Nitride 4150 Cmv Brl

The Rosco Manufacturing Bloodline 300 Blackout barrel is a short, handy upper receiver component purpose-built for .300 Blackout AR platforms. At 7.50 inches, this nitride-finished barrel strikes a practical balance between ballistic performance and overall weapon length—ideal for suppressed subsonic loads, close-quarters hunting, or home defense setups where compact handling matters. The 4150 CMV steel construction with nitride treatment delivers barrel hardness and corrosion resistance that handles frequent shooting without babying.

300 Blackout has become the go-to intermediate cartridge for short-barreled AR builds, and this Rosco barrel is engineered to maximize what that round can deliver from a compact package. Whether you're running supers through an unsuppressed rifle or whisper-quiet subsonic ammunition down range, the Bloodline line represents Rosco's no-nonsense approach to barrel manufacturing—solid metallurgy, tight tolerances, and proven reliability without the premium price tag.

Drop this barrel into your AR-15 upper and you've got a capable, maneuverable platform ready for the range, field, or duty use. Rosco barrels have earned respect among serious shooters for standing up to volume fire and maintaining accuracy when it counts.

Key Features

• 7.50-inch length optimized for .300 Blackout performance in compact AR builds
• 4150 CMV steel with nitride finish for hardness and corrosion resistance
• Designed for both supersonic and subsonic .300 Blackout ammunition
• Tight tolerances and solid construction from a trusted barrel manufacturer

Specifications

Frequently Asked Questions

What AR-15 upper will this barrel fit?

This .300 Blackout barrel is a standard AR-15 upper receiver component. It will work with any AR-15 upper compatible with .300 Blackout barrels—confirm your upper accepts this caliber before installation.

Is this barrel good for suppressed shooting?

Yes. The 7.50-inch barrel works excellently with .300 Blackout subsonic loads and a suppressor, delivering the compact, quiet platform that makes this caliber popular for that use case. It also handles supersonic rounds reliably.

What finish does this barrel have?

The barrel features a nitride finish, which provides hardness and corrosion resistance for durability and low maintenance through regular shooting.