SIG Sauer SIGM400
SIG Sauer's AR-15-derived carbine family for military, law enforcement, and civilian use.
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SIG Sauer produces the SIGM400 line of carbines, which are air-cooled, direct impingement gas-operated, and magazine-fed. Based on the AR-15 design, this firearm comes in 5.56×45mm NATO or .300 AAC Blackout, with either a fixed or telescoping stock.
Design details
The SIGM400 is a semi-automatic firearm that operates from a closed bolt with a direct impingement gas system. It comes in both rifle and pistol configurations, targeting law enforcement, military, and civilian users. Rifle versions are available in 5.56×45mm NATO with threaded barrels of 14.5, 16, 18, or 20 inches, or in .300 AAC Blackout with 9 or 16-inch threaded barrels.
California-compliant featureless models exist for each caliber. The .300 AAC Blackout variant is designed for optimal use with suppressors, which SIG Sauer also produces. The SIGPM400 Elite PSB pistol is offered in 5.56×45mm NATO with an 11.5-inch barrel and in .300 AAC Blackout with a 9-inch barrel, both equipped with a Pistol Stabilizing Brace.
Variants
The SIG Sauer SIGM400 line includes the M400 Classic, SRP, Tread, Elite, Predator rifles, and the Elite PSB pistol. The M400 PRO is an upgraded model in 5.56×45mm NATO, with a cold-hammer forged barrel, a two-stage match trigger, a free-floated M-LOK handguard, a folding front sight, and a redesigned six-position collapsible stock.
The M400 TREAD is a more affordable variant, named after the Gadsden flag and its motto. It uses a 16-inch hammer-forged barrel with a 1:8 twist and proprietary Taper-Lok muzzle threading, a mid-length low-profile gas system, a 15-inch free-floated handguard, and a Magpul SL-K adjustable stock. Its pistol grip can store AA, CR123A, or CR2032 batteries, but it comes without iron sights.
More in FN, Heckler & Koch, SIG and Mauser Firearms
Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: SIG Sauer SIGM400 (CC BY-SA 4.0).
- Word definitions: the Codexery glossary, each quoted from its Wikipedia article.
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