SIG SAUER RSAR999 USSOCOM MCX-Rattler LT 5.56 NATO Pistol

The SIG SAUER RSAR999 USSOCOM MCX-Rattler LT in 5.56 NATO is a compact, high-performance pistol born from a 2022 USSOCOM contract, designed for operators needing maximum firepower in a concealable package. Featuring a 7.75-inch cold hammer-forged barrel and a 30+1 capacity, this PDW-style firearm delivers exceptional modularity with barrel interchangeability for 7.62×39 configurations and SLH suppressor compatibility. Its Cerakote finish, 3-position telescoping stock or folding PCB brace, and included Pelican case make it a rare, limited-quantity build for tactical enthusiasts and collectors.

Crafted for elite performance, the RSAR999 boasts a short-stroke piston system, a 1:7 twist rate for optimal bullet stability, and a 2-stage Matchlite Duo trigger for precise control. The optic-ready design with steel flip-up sights, a smooth side deflector, and a barricade stop enhances its versatility for close-quarters engagements. Compared to standard MCX-Rattler models, this SWG configuration—offered as a contract overrun—includes premium accessories like Magpul dual QD slings and a single-point adapter, ensuring it meets USSOCOM’s stringent standards for concealability and firepower.

Ideal for tactical shooters, collectors, or those seeking a SOCOM-grade firearm, the RSAR999 excels with its 6.1 lb weight and 7.4-inch height, offering a balanced feel for rapid deployment. The chrome-lined barrel and 5/8-24 threaded muzzle with a tapered shoulder ensure suppressor-ready performance, while the included certificate of authenticity adds historical value. This pistol is a unique opportunity to own a piece of USSOCOM history, blending cutting-edge design with proven battlefield reliability.

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