SIG Sauer SIGM400
| SIG Sauer SIGM400 series | |
|---|---|
 Sig Sauer M400 series rifle | |
| Type | Semi-automatic rifle Carbine |
| Place of origin | United States |
| Service history | |
| In service | 2011–present |
| Used by | See users |
| Wars | War in Iraq (2013–2017) Islamic State insurgency in Iraq (2017–present) Operation Containment |
| Production history | |
| Designed | 2000s |
| Manufacturer | SIG Sauer |
| Produced | 2011–present |
| Specifications | |
| Mass | 7.6 pounds (3.4 kg) |
| Barrel length | 11.5–20 inches (29–51 cm) (5.56×45mm) 9–16 inches (23–41 cm) (.300 AAC) |
| Cartridge | 5.56×45mm NATO .300 AAC Blackout |
| Action | Direct gas impingement system, rotating bolt |
| Feed system | STANAG magazines |
The SIGM400 is a family of firearms manufactured by SIG Sauer.[1] The M400 is an air-cooled, direct impingement gas-operated, magazine-fed carbine based on the earlier AR-15 rifle.[2] It is chambered for either 5.56×45mm NATO or .300 AAC Blackout cartridges, and can have a fixed or telescoping stock.[3]
Design details
[edit]Operating mechanism
[edit]The SIGM400 is a semi-automatic firearm firing from a closed bolt and uses a direct impingement gas system.[3]
Features
[edit]The M400 is offered as either a rifle or as a pistol and is intended for law enforcement, military and civilian markets. Rifles are chambered in either 5.56×45mm NATO with 14.5-inch (37 cm), 16-inch (41 cm), 18-inch (46 cm), or 20-inch (51 cm) threaded barrels, or .300 AAC Blackout with 9-inch (23 cm) or 16-inch (41 cm) threaded barrels. There are California compliant ("featureless") models for both.[3] The .300 AAC Blackout model is tailored specifically for efficient use with suppressors, which SIG Sauer also manufactures.[citation needed]
The SIGPM400 Elite PSB pistol is chambered for 5.56×45mm NATO with an 11.5-inch (29 cm) barrel and is chambered for .300 AAC Blackout with a 9-inch (23 cm) barrel. Both use a Pistol Stabilizing Brace accessory.[3][needs update]
Variants
[edit]Variants include rifles like the M400 Classic, SRP, Tread, Elite, or Predator, and the Elite PSB pistol.
M400 PRO
[edit]The M400 PRO is an improved version of the SIG M400 chambered in 5.56×45mm NATO. Changes include a cold-hammer forged barrel, 2-stage match trigger, free-floated M-LOK handguard, folding front sight, and an updated 6-position collapsible stock.[4]
M400 Tread
[edit]The M400 TREAD is a budget-oriented variant of the M400 named for the Gadsden flag and its slogan "Dont Tread On Me". Chambered in 5.56×45mm NATO, it features a 16-inch hammer-forged barrel with a 1:8 twist and proprietary Taper-Lok muzzle threading, mid-length low-profile gas system, 15-inch free-floated handguard,[5] and a Magpul SL-K adjustable stock.[6] The pistol grip can hold AA, CR123A, or CR2032 batteries.[5] Iron sights are not included.
Users
[edit]
Brazil: M400 PRO used by Civil Police of Rio de Janeiro State.[7]
Iraq: Iraqi Special Operations Forces[8][9]
Oman: Omani Military[9]
Philippines: M400 PRO used by Philippine Army as a replacement for the M16A1.[10]
United States
See also
[edit]- Heckler & Koch HK416 – German assault rifle
- SIG Sauer SIG516 – Family of rifles manufactured by SIG Sauer
- SIG MCX – Family of rifles manufactured by SIG Sauer
- M4 carbine – American assault rifle
References
[edit]- ↑ "SIGM400". SIG Sauer. Archived from the original on 18 February 2020. Retrieved 13 March 2017.
- ↑ "SIG SAUER's M400 Predator". gunsmagazine.com. Archived from the original on 14 October 2017. Retrieved 27 February 2017.
- 1 2 3 4 "SIGM400 Predator". sigsauer.com. Archived from the original on 28 February 2017. Retrieved 27 February 2017.
- ↑ "2019 Defense Strategies: Products" (PDF). SIG SAUER. 2019. pp. 30–31.
{{cite web}}: CS1 maint: url-status (link) - 1 2 Massimilian, Andy (30 January 2019). "Review: SIG Sauer M400 Tread". Shooting Illustrated. National Rifle Association. Retrieved 5 December 2025.
{{cite web}}: CS1 maint: url-status (link) - ↑ "M400 TREAD 1.0". www.sigsauer.com. Retrieved 5 December 2025.
- ↑ "Conheça os novos fuzis da Polícia Civil do Rio". O Globo. 8 July 2023. Archived from the original on 12 July 2023.
- ↑ "ISOF Arms & Equipment Part 1 – Personal Equipment". Armament Research Services (ARES). 27 November 2016.
- 1 2 "Is This the Ultimate AR-15 Rifle of All Time?". 20 July 2019.
- ↑ "ORD PABAC2-005-24 Carbine, 5.56mm Assault Rifle 15 Platform Acquisition Project of the Philippine Army".
- ↑ "Detroit Police Department SWAT Adopts SIG SAUER M400 Rifles | Soldier Systems Daily". Soldier Systems Daily. 19 September 2018. Retrieved 5 December 2025.
- ↑ "Contract Information". Florida Department of Financial Services. Retrieved 5 December 2025.
- ↑ "Detroit SWAT picks Sig Sauer M400 in rifle contract".
- ↑ "Philadelphia SWAT Adopts SIG SAUER M400 Pro Rifles -". 3 January 2019.
- ↑ "Vermont State Police Adopts SIG SAUER M400 Pro Rifles as Patrol Rifle". www.sigsauer.com. Retrieved 5 December 2025.