Sig Sauer MCX Rattler 300 Blackout Upper Receiver Kit – UAMCX-5B-300-BLK-TAP


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SigSauer MCX Rattler 300 Blackout Upper Conversion Kit

The Sig Sauer MCX Rattler AR conversion kit with a 5.5″ barrel length comes with everything needed to put on any standard MIL-SPEC AR lower. This conversion kit includes: a 5/8″ x 24 threaded barrel, a complete bolt carrier group, a Sig Sauer MCX upper, side folding AR buffer tube knuckler, 90 degree muzzle adapter for standard non Sig Sauer suppressors or muzzle devices, AR Two-Stage Matchlite DUO trigger kit and 1913 low profile QD socket with hardware and adjustable flip up iron sights.

The SIG Matchlite Duo trigger unit provides a crisp and clean feel, and a new tapered bolt lug design extends bolt life while resulting in smoother cycling. The MCX Rattler upper receiver assembly features a standard free-floating M-LOK handguard with a top picatinny rail for sight and optic, as well as a short-stroke piston system and unique internal recoil system that eliminates the M4-style buffer tube resulting in a light-recoiling and compact platform able to be configured for any task.