$1,903.00 $1,679.99

Item #: RMCX-300B-16B-TFSAL-P

Introducing the SIG MCX™. Engineered for 300BLK. Built from the ground up to be silenced, light and short. A breakthrough in modularity. The result of years of toil and sweat, the SIG MCX is proof that the dawn of a new era doesn’t happen overnight.

The SIG MCX is an innovative weapon system built around a battle-proven core: SIG’s gas-operated, short-stroke piston system. Trust it for the outstanding performance, no matter the conditions, that you’ve come to expect from the leading name in firearms.

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SKU: RMCX-300B-16B-TFSAL-P Categories: , , , ,



Even while in the field, you can configure the SIG MCX as needs or conditions change. The combination of the 13″ monolithic upper receiver and handguard create a 17 3/4″ continuous top rail. The upper is backwards compatible with any mil-spec AR lower, allowing you to upgrade your existing AR platform to the SIG MCX. The AR upgrade kit includes side-folding stock assembly and adapter.

The SIG MCX stands as the first rifle built to be silenced from the ground up. It also accepts a broad array of accessories, enabling you to build a complete weapon system for any scenario or environment.


  • Ambidextrous Charging Handle and Controls
  • Reinforced, Monolithic Upper Receiver
  • Easily Change Stock, Barrel, Handguard and Caliber
  • Free-Floating Barrel Design


Additional information

Weight 9 lbs
Dimensions 47 × 12 × 5 in