Description
The Sentinel’s fully shrouded, snag-free flash hiding performance scaled for .30 caliber. The Breek Arms Plan B Sentinel Caged Flash Hider in 5/8×24 brings the same closed-tine cage design, NVG-friendly flash containment, and Plan B/Atlas mount compatibility to .308, .300 BLK, and other .30-caliber platforms — with the same 2.15-inch overall length and pin-and-weld capability as the 5.56 variant.
The Breek Arms Plan B Sentinel Caged Flash Hider is a closed-tine, fully shrouded .30-caliber muzzle device machined from 4140 hardened steel with a nitride finish, designed for 5/8×24-threaded .30-caliber barrels with Plan B/Atlas suppressor mount compatibility and pin-and-weld capability.
Four features define the Sentinel’s performance for .30-caliber duty and suppressor-host builds. The closed-tine cage eliminates the snagging hazard of open prong designs for gear, brush, and vehicle operations while containing the muzzle flash from .30-caliber cartridges — where the larger powder charge produces a more visible fireball than 5.56 — within the shroud for a compact, NVG-friendly signature. Plan B and Atlas mount compatibility provides fast, tool-free suppressor transitions from the same muzzle device across calibers, allowing the shooter to use a single suppressor host across multiple platforms sharing the Plan B ecosystem. The Sentinel is engineered for pin-and-weld installation on barrel lengths where the muzzle device brings the configuration to the 16-inch federal minimum, providing a permanent, flush solution. 4140 hardened steel with nitride finish provides long service life at the muzzle end where heat, blast, and mechanical wear concentrate.
Compatible with 5/8×24-threaded .30-caliber barrels. Plan B and Atlas suppressor mount compatible. P/W capable. Peel washer included.
4140 hardened steel, nitride finish. 2.15″ overall length. Weight: 1.8 oz. Made in the USA.
Built for .308, .300 BLK, and .30-caliber builds running Plan B or Atlas mounts requiring a snag-free caged flash hider for duty, NVG, or suppressor-host applications.
By Breek Arms. Made in the USA. Peel washer included. Standard Breek Arms warranty applies.
Specifications
WARNING*
– Sentinel Flash Hiders using .223/5.56 ammunition have been tested and rated for 7.5″ barrels and longer
– Sentinel Flash Hiders using .308 ammunition have been tested and rated for 10″ barrels and longer
– The use of PEEL WASHERS OR SHIMS for installing muzzle devices is HIGHLY recommended
PRODUCT SKU: BRK4421
