First Look: SIG Sauer MCX

sig_sauer_mcx_fBuilding off the success of its MPX submachine gun, SIG Sauer has introduced a new firearm that combines similar modularity with a purpose-built, short-barreled, suppressed, lightweight rifle-caliber system.

Named the MCX, the new rifle is engineered to optimize performance with the .300 Blackout cartridge and with suppressors. It's arrival is perfectly timed with the release of SIG Sauer's new Elite Performance .300 AAC Blackout ammunition and SRD suppressors.

The SIG MCX features an auto-regulating gas system that allows for seamless transition between firing subsonic and supersonic loads. Running supersonic loads through a suppressor with the MCX will not damage the firearm or negatively affect reliability.

The MCX's modular design also makes it completely mission-adaptable. Swapping from .300 Blackout to 5.56 NATO only requires the shooter to change out the barrel and op rod, while converting to 7.62x39mm entails an additional bolt face change. Barrel lengths can also be adjusted, and 16- and 9-inch versions will be available initially.

Notably, the MCX features an innovative recoil assembly that does not require a buffer tube, giving shooters the ability to utilize side-folding stocks. It incorporates a full-length Picatinny top rail for optics and accessories, and SIG's iron sights come standard. The MCX's upper is compatible with all Mil-Spec AR-15 lowers and, when paired with a SIG MCX Stock Kit, allows users to fully upgrade their legacy system.

There will be three initial variants of the MCX available to civilians: a semiauto rifle, a short-barreled rifle (SBR) and pistol configurations. All of these will be offered in .300 Blackout, 5.56 NATO or 7.62x39mm, with caliber conversions available immediately.

"We've built a team of the best minds in the industry, when it comes to silencer technology, rifle engineering and the .300 Blackout cartridge," said Jeff Creamer, Executive Director and General Merchandise Manager for SIG SAUER, Inc. "The end result is a technological leap forward in ergonomics, modularity, cartridge performance, and sound reduction."

Each of the MCX models will have aluminum KeyMod handguards, ambidextrous AR-style controls and an ambidextrous charging handle. All MCX rifles will utilize standard STANAG magazines and come with an upper receiver with hardened replaceable wear points. These include a cam path wear insert, a feed ramp insert, a removable/replaceable deflector and charging handle latch point inserts.

Both the rifle and SBR variants will be offered with a choice of four stocks: a low profile, side-folding skeletonized stock, a telescoping stock, a tubular side-folding stock or a folding telescopic stock. The pistol configurations come with a side-folding version of SIG's SBX Pistol-Stabilizing Brace.

The SIG MCX rifle version sports a 16-inch cold hammer-forged barrel and is available for $1,866, while the SBR variant features a 9-inch barrel and is available for $2,058. The MCX pistol also utilizes a 9-inch barrel and is available for $2,132.

For more information, keep your eye out for a full review in an upcoming issue of Guns & Ammo and check out the photos below.



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