Home / Gun Parts / AR-15 Parts / Upper Parts / Barrels / BAR 5 300 – 5″ 300 BLACKOUT MICRO 1:5 BAR 5 300 – 5″ 300 BLACKOUT MICRO 1:5Login 5″ 300 B.O. barrel featuring a 1:5 twist rate. Designed for compact AR builds requiring reliable performance and accuracy. SKU: BAR 5 300 Categories: .300 Blackout, All Products, AR-15 Barrels, AR Barrels, Barrels Product ID: 339393 Description Description Platform: AR15 Chambering: .300 AAC Blackout Twist Rate: 1:5 Overall Length: 5″ Muzzle Thread: 5/8-24 Gas System Length: Micro Gas Profile Type: Mid Material: 4140 GBQ Steel Finishing: Black Nitride MADE IN USA