Brownells Brownells Brownells 75th Anniversary - A Shooting Heritage

Converts Your AR To A Hard-Hitting .30 Caliber Round With No Other Modifications

Direct replacement for the standard .223/5.56mm barrel converts your AR-15 to the high-performance 300 AAC Blackout (300BLK) cartridge. The 300 AAC lets you upgrade your rifle to 7.62 x 39 ballistics, while retaining the standard AR-15/M16 bolt, carrier, and magazine at its full capacity, with no additional modifications. 1-7" rifling accepts bullet weights from 110 gr to 220 gr, and 5/8"-24 muzzle threads accept popular AR-.308 flash suppressors and muzzle brakes. Three models available, 16", 12.5" and 8.2" long and treated inside and out with CMMG’s "Wasp" nitriding process for outstanding resistance to wear and corrosion. 16" barrel has the gas port in the standard position for use with all M4-length gas systems and supersonic ammunition. 12.5" & 8.2" barrels have the gas port positioned for use with pistol-length gas systems.


AR-15, Issue:09, Page:016
Big Book Catalog, Issue:66, Page:016

SPECS: Hardened 4140 chrome-moly steel, Wasp nitride finish, matte black .750" O.D. at gas port.5/8-24 muzzle threads. 

CMMG - AR15/M16 300 BLACKOUT BARRELS

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3 Item(s)

$199.99

In Stock

Cartridge: 300 AAC Blackout

Barrel Weight: 2.205 lbs

Contour: Medium

Finish: Black

Length: 16

Muzzle: .625, ...

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$179.99

In Stock

Cartridge: 300 AAC Blackout

Contour: Medium

Finish: Nitride

Length: 12.5

Twist: 1-7

$169.99

Out of Stock

Cartridge: 300 AAC Blackout

Contour: Medium

Finish: Nitride

Length: 8.2

Twist: 1-7