SIG MCX
2010s multi-configuration firearm family by SIG
The SIG MCX is a family of rifles designed and manufactured by SIG Sauer, produced in both selective fire assault rifle configuration and semi-automatic only models, and features a short-stroke gas piston system, which is inherited from the earlier SIG MPX submachine gun.
The semi-automatic only variant of the MCX is available in rifle, carbine, short-barreled rifle, and pistol (short-barreled rifle configured with a pistol brace or without a buttstock at all) configurations.
The MCX served as the basis for SIG Sauer's NGSW-R submission, the SIG MCX-SPEAR, designed to chamber the .277 Fury cartridge, and was formally adopted as the M7 rifle by the U.S. Army in 2022.
History
The SIG MCX was introduced at SHOT Show 2015. The rifle was originally designed by SIG USA, the subsidiary of SIG Sauer based in New Hampshire.
In 2016, SIG recalled some of the rifles that had the first-generation bolt carrier group.
The MCX has been used by various SWAT teams and militaries, including the Ukrainian Armed Forces during the Russian Invasion of Ukraine.
An MCX was used in the 2016 Orlando nightclub shooting, which was the deadliest mass shooting in U.S. history, until exceeded by the 2017 Las Vegas shooting.
Design details
The SIG MCX series features a short-stroke gas piston with dual recoil spring system to reduce recoil and improve the reliability of the rifle; this was based on the design of the earlier SIG MPX. The MCX features a system that enables 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.
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This entry incorporates text from “SIG MCX” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.