Brownells XM177E2 11.50" Classic Upper 5.56x45mm 1:12 Carbine-Length w/BCG, Black

The XM177E2 upper receivers a redesigned for retro builds, drawing inspiration from popular carbine configurations. The muzzle is equipped with a classic XM177E2 moderator-inspired flash hider, featuring radial ports. Unlike the original XM177 muzzle device, which functioned as a suppressor, this component serves as a flash hider and is affixed to a lightweight 11-1/2 inches barrel. For optimal performance with 55 grain bullets, select a 1:12 twist rate. The front sight base is not F-marked, ensuring alignment of the round, tapered front sight post with the carry handle rear sight. The black carbine handguards are crafted to closely replicate the original CAR handguards. These barrel assemblies include a tapered slip ring, appropriate for carbines of this type. The upper receiver is equipped with a proper ejection-port cover, featuring a flat external bump, distinct from standard A2 models. The receiver itself is styled after the M16A1, incorporating a forward assist but lacking a shell deflector. The rear sight is the standard A1 aperture, adjustable with a cartridge or tool. The included Bolt carrier group is a manganese phosphate mil-spec BCG with a chrome-lined interior. M16A1 upper receiver lacking shell deflector Barrel with a length of 11-1/2 inches, chambered for 5.56x45mm ammunition 1:12 rifling twist rate with chrome-lined bore and chamber Ejection port cover for M16A1 Teardrop forward assist A1 rear sight component assembly Subjected to magnetic particle inspection and high-pressure testing Black polymer handguards equipped with integrated heat shields for carbine models Manganese phosphate mil-spec Bolt carrier group featuring a carpenter 158 bolt