SIG Sauer SIGM400

The SIGM400^[1] is a family of firearms manufactured by SIG Sauer. The rifle is based on the earlier AR-15 rifle.^[2][3]

Design details

Operating mechanism

The SIGM400 is a semi-automatic firearm in either rifle as the SIGM400 Predator or pistol as the SIGPM400 Elite PSB, intended for civilian and law enforcement markets. It fires from a closed bolt and uses a direct gas impingement system.^[2]

Features

The SIGM400 Predator is a rifle while the SIGPM400 Elite PSB is a pistol. Sig Sauer uses 416 stainless steel in the barrel of the SIGM400 series The rifles come in either 5.56×45mm NATO with 18" barrels or .300 AAC Blackout with 16" barrels which are threaded 12x28 tpi for suppressor use and rifled at a 1:8 twist. There are California compliant models for both.^[2] The .300 AAC Blackout model is tailored specifically for efficient suppressed use. The picatinny rail supports optical, electro optical, or iron sights. A two stage match quality trigger is used.^[3] Sig Sauer also manufactures suitable suppressors.

The SIGPM400 Elite PSB pistol has calibers of 5.56×45mm NATO with an 11.5" barrel and .300 AAC BLK with a 9.5" barrel. Either than use the Pistol Stabilizing Brace accessory.^[2]

Ergonomically, the SIGM400 is patterned after the AR-15-type rifle. It has a safety lever on the left side, to be used by the thumb of the shooting hand. Some newer models have an ambidextrous safety selector. The front gas block is railed to accept the front sight with a flip-up sight post.

All models accept AR-15-style box magazines. The rifle is hammer-fired with a single-stage trigger in most models. Some models include a two-stage trigger from the factory.

The SIGM400 has a telescoping skeletonized buttstock. The ACE-style stock moves forward and rearward in 6 positions. A spring-loaded release underneath the buffer tube area locks into each position.

See also

• Heckler & Koch HK416

References

External links