Building on popular carbine configurations, these XM177E2 Upper Receivers are perfectly suited for your next retro build.
The muzzle of the XM177E2 Upper Receiver features a classic XM177E2 moderator-inspired flash hider, with ports around its circumference. Unlike the original XM177 device, which functioned as a suppressor, this updated muzzle device serves solely as a flash hider.
Attached to the upper is a lightweight barrel available in 11.5 or 12.7 inches. The 12.7-inch model has its flash hider pinned and welded, bringing the overall barrel length to the required 16 inches for a rifle.
Barrel options include a 1:12 twist for 55-grain bullets and a 1:7 twist for 62-grain or heavier rounds. The front sight base is not F-marked, ensuring the round, tapered front sight post aligns correctly with the carry handle rear sight. The black carbine handguards are designed to closely resemble the original CAR handguards, and the barrel assemblies feature a tapered slip ring, appropriate for carbines of this style.
The upper also includes an authentic ejection port cover with a flat external "bump," distinct from the standard A2 design. The receiver itself is modeled after the M16A1 style, featuring a forward assist but no shell deflector. The rear sight is a standard A1 aperture, easily adjustable with a cartridge or tool. The included bolt carrier group is a proper manganese phosphate mil-spec BCG with a chrome-lined interior.
Key features of the XM177E2 Complete Upper Receivers:
- M16A1 upper receiver without shell deflector
- XM177 flash hider with proper grenade ring
- 11.5” or 12.7” 5.56x45mm NATO barrel
- 12.7” configuration features a pinned and welded muzzle device, making it 16”+
- 1-12 or 1-7 twist & chrome bore & chamber
- M16A1 ejection port cover
- Tear drop forward assist
- A1 rear sight assembly
- Carbine black polymer handguards with heatshields
- Manganese phosphate mil-spec bolt carrier group with 9310 bolt
