This retro A1 AR-15 receiver has the ejection port machined larger allowing big bore cases to cleanly eject.
Works with .458 SOCOM, 375 SOCOM, 358 SOCOM, 50 Beowulf, 450 Bushmaster, etc.
For use on standard modern 1/4″ pin AR-15 lowers. Will not work on older SP1 Colt lowers.
Black annodized, no forward assist or case deflector. Old style A1 rear sight and door cover included and installed.
No caliber markings.