The Brownells XM177 Flash Hider & Grenade Ring is a faithful reproduction of the iconic Vietnam-era muzzle device, purpose-built for AR-15 retro carbine builds and historical rifle projects. If you're assembling a vintage-correct XM177, Colt Model 609, 619, 629, 630, or USAF GAU-5A platform, this is the authentic piece that belongs on the end of your barrel. Machined from 8620L steel with a manganese phosphate finish, it combines period-accurate proportions with modern manufacturing precision—delivering the look and flash-hiding performance of the original without compromise.

The design captures the distinctive flash hider cuts and integrated grenade ring that defined early short-barrel AR platforms. The grenade ring allows mounting of the XM177-compatible 40mm grenade launcher, a feature essential to any correct retro build. Whether you're documenting a specific military variant or simply appreciate the mechanical elegance of Cold War-era small arms, this Brownells reproduction handles both aesthetics and function.

Weighing in at 4.335 inches without the ring and 4.45 inches with it fully assembled, the XM177 fits standard 1/2-28 AR muzzle threads found on most carbine barrels. Installation is straightforward—index it on your barrel and torque to spec. The manganese phosphate finish is robust and will patina naturally over time, adding character to a well-used rifle. For shooters building or restoring a period rifle, this is the muzzle device that gets the details right.

The Brownells XM177 Flash Hider & Grenade Ring is a faithful reproduction of the iconic Vietnam-era muzzle device, purpose-built for AR-15 retro carbine builds and historical rifle projects. If you're assembling a vintage-correct XM177, Colt Model 609, 619, 629, 630, or USAF GAU-5A platform, this is the authentic piece that belongs on the end of your barrel. Machined from 8620L steel with a manganese phosphate finish, it combines period-accurate proportions with modern manufacturing precision—delivering the look and flash-hiding performance of the original without compromise.

The design captures the distinctive flash hider cuts and integrated grenade ring that defined early short-barrel AR platforms. The grenade ring allows mounting of the XM177-compatible 40mm grenade launcher, a feature essential to any correct retro build. Whether you're documenting a specific military variant or simply appreciate the mechanical elegance of Cold War-era small arms, this Brownells reproduction handles both aesthetics and function.

Weighing in at 4.335 inches without the ring and 4.45 inches with it fully assembled, the XM177 fits standard 1/2-28 AR muzzle threads found on most carbine barrels. Installation is straightforward—index it on your barrel and torque to spec. The manganese phosphate finish is robust and will patina naturally over time, adding character to a well-used rifle. For shooters building or restoring a period rifle, this is the muzzle device that gets the details right.