In service 2015–present Produced 2015–present | Place of origin United States | |
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Used by Netherlands Maritime Special Operations ForcesSC&O19 CTSFOs |
The SIG MCX is a weapon series designed and manufactured by SIG Sauer, featuring a short-stroke gas piston system, carried over from the SIG MPX submachine gun. It is made in both semi-automatic and selective fire configurations. It is available in rifle, short-barreled rifle, and pistol configurations.
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Built at SIG's New Hampshire factory, the MCX was "engineered from the ground up to be silenced, light and short" according to a SIG Sauer brochure.
In 2016, SIG recalled some weapons with the first generation bolt carrier group.
Design
The SIG MCX series features a short-stroke gas piston system to reduce recoil and improve the reliability of the weapon; this was based on the design of the earlier SIG MPX. The MCX features a system that allows for conversion between 5.56×45mm NATO, .300 AAC Blackout and 7.62×39mm ammunition, using standard 5.56 mm STANAG magazines for 5.56×45mm NATO and .300 AAC Blackout, and specially designed STANAG-compatible magazines for 7.62×39mm. The MCX is designed to deliver optimal performance with .300 AAC Blackout and an optional suppressor.
The barrel's profile is tapered at the crown to allow the installation of muzzle devices and direct-thread sound suppressors without the use of washers that degrade performance and allows the devices to self-center on installation. The barrel can be changed in a matter of seconds to another length or a different caliber. Additionally the barrels are nitride coated for corrosion resistance. It features hardened steel wear points.
All MCX variants have a forend made of aluminum with a KeyMod system to add accessories. Controls are mostly ambidextrous including the charging handle but not the bolt release. Four types of stocks are available for the MCX carbine.
SIG designed the upper receiver to be compatible with standard AR-15 and M16 lower receivers. The overall layout of the two rifles is similar.
Variants
Users
Criminal use
A SIG MCX was used in the 2016 Orlando nightclub shooting, which was the worst mass shooting in U.S. history.