SIG Sauer SIGM400

SIG Sauer SIGM400 series
Sig Sauer M400 series rifle
TypeSemi-automatic rifle
Carbine
Place of originUnited States
Service history
In service2011–present
Used bySee users
WarsWar in Iraq (2013–2017)
Islamic State insurgency in Iraq (2017–present)
Production history
Designed2000s
ManufacturerSIG Sauer
Produced2011–present
Specifications
Mass7.6 pounds (3.4 kg)
Barrel length11.5–20 inches (29–51 cm) (5.56×45mm)
9–16 inches (23–41 cm) (.300 AAC)

Cartridge5.56×45mm NATO
.300 AAC Blackout
ActionDirect gas impingement system, rotating bolt
Feed systemSTANAG magazines

The SIGM400 is a family of firearms manufactured by SIG Sauer. The M400 is an air-cooled, direct impingement gas-operated, magazine-fed carbine based on the earlier AR-15 rifle. It is chambered for either 5.56×45mm NATO or .300 AAC Blackout cartridges, and can have a fixed or telescoping stock.