SIG MPX

Summary

The SIG MPX is a gas-operated submachine gun designed and manufactured by SIG Sauer, and is primarily chambered in 9×19mm Parabellum. It is a gas-operated firearm featuring a closed, rotating bolt.[2] These design features, rare in submachine guns, were chosen to enhance the safety of the user and to have a more reliable firearm.[3] It was designed in 2013 and was released to the general public in 2015.[4] It features the SIG Sauer short stroke push-rod gas system to reduce the recoil and improve the reliability of the weapon.

SIG Sauer MPX
TypeSubmachine gun
Place of originUnited States[1]
Service history
In service2015–present
Production history
Designed2013
ManufacturerSIG Sauer
Produced2015–present
VariantsSee Variants
Specifications
Mass2.7 kg (6.1 lbs)
Length425 mm (16.7 in), stock folded
610 mm (24.0 in), stock extended
Barrel length114 mm (4.5 in)
165 mm (6.5 in)
203 mm (8 in)

Cartridge9×19mm Parabellum
ActionShort-stroke gas-operated, closed rotating bolt
Rate of fire850 RPM
Feed system10-, 20-, 30- or 35-round detachable box magazine, 50 round drum magazine

The MPX, in its second generation, features a system that would allow for conversion from 9mm to .357 SIG or .40 S&W. However, since its inception, first party conversion kits have not been made available for either of the two production generations of the gun.[5]

SIG Sauer also used the same gas piston system to develop the SIG MCX carbine.

Design details edit

 
SIG MPX with Republic of China Marine Corps Special Service Company Operator

The standard variant of the MPX comes with an 8.0 inch (20.3 cm) barrel and is chambered in 9×19mm Parabellum. It comes with a collapsible stock and a free-floating rail. It has a cyclic rate of fire of 850 rounds per minute (RPM).[6][7]

The MPX is also available with different barrel lengths, ranging from 114 to 406mm (4.5- to 16-inch).[8] The MPX submachine gun is only available for military and law enforcement use, while a semi-automatic only version is also available for the civilian market.

The semi-automatic version of the weapon can be registered as a short-barreled rifle in most states in the United States.[5]

Features edit

The standard MPX submachine gun comes with no sights and a full-length Picatinny rail system on the top of the weapon. Gen 2 MPX's come with a flat faced Timney trigger and M-LOK rail.

The MPX has a short-stroke gas piston system in order to increase the accuracy of the weapon which operates from a closed bolt.[2] It is designed in this way to prevent water or dirt from entering the chamber and causing malfunctions as well as to use a suppressor with greater ease.[9] It features an ambidextrous selector switch for fully automatic (law enforcement/military models) and semi-automatic. It also features an ambidextrous bolt release and ambidextrous magazine release. The barrel is free-floating and is surrounded by polymer/steel Picatinny rail (later M-LOK) mounts.

The charging handle of the weapon is at the back of the weapon, based on the AR-15 design. This is to ensure that cocking the weapon does not interfere with any optics mounted onto the Picatinny rail. The weapon's rails are made out of cast steel and the standard weapon overall weighs 2.1 kilograms (4.6 lb).

Variants edit

Selective fire configurations edit

 
SIG MPX

MPX (Standard variant) edit

A pistol variant with a three-position collapsible arm support with a stock-like appearance, three-position fire selector if it supports full automatic and an 14” blind pined and welded muzzle brake 16”, 8.0, 6.0 4.5 inch barrel.[10]

MPX-K (Compact variant) edit

A compact variant with a 114 mm (4.5 inch) barrel.

MPX-SD (Integrally suppressed variant) edit

A fully suppressed variant with an MP5SD-like integral suppressor, a longer fore-end and a 203 mm (8.0 inch) barrel.

Semi-automatic only configurations edit

MPX Pistol (Pistol variant) edit

A semi-automatic only pistol variant with no stock and a 203 mm (8.0 inch) barrel.

MPX PSB (Pistol variant) edit

A semi-automatic only pistol variant with a SIG SBX pistol stabilizing brace and an 203 mm (8.0 inch) barrel. In the US in 2015 the BATFE warned users of weapons using SIG stabilizing braces that shouldering a weapon fitted with a brace constituted the making of a Title II NFA weapon, reversing a prior ruling that it did not.[11] In early 2017, however, the BATFE withdrew this opinion.[12]

MPX-K (Pistol variant) edit

A semi automatic only pistol variant with a 114 mm (4.5 inch) barrel.[13]

MPX-C (Carbine variant) edit

A semi-automatic only carbine variant, featuring a 165 mm (6.5 inch) barrel with a 241 mm (9.5 inch) muzzle device permanently welded to it, which is actually a modified version of the baffle core of the integrally suppressed variant. SIG contended that this device was a muzzle brake, but in 2013 the BATFE ruled that the component was a suppressor, and classified the MPX-C as possessing an integral suppressor and thus as a Title II NFA weapon. The BATFE rejected an appeal against this ruling in February 2014; SIG responded by filing a civil lawsuit against the BATFE,[14] alleging they had acted in an "arbitrary and capricious manner". In September 2015, Federal Judge Paul Barbadora upheld the BATFE's ruling.[15]

As a result of this SIG has announced a carbine variant with a 406 mm (16 inch) barrel without the muzzle device, designated as the MPX PCC.[3]

Users edit

Country Organization/Notes Reference
  Hong Kong Hong Kong Police Force, Hong Kong Correctional Service [16]
  India National Security Guards [17]
  Indonesia Detachment 88 [18]
  Malaysia Malaysian Army [19]
  Thailand Royal Thai Police [20]
  United States United States Army: US Army Contracting Command purchased 4.5" and 8" barreled variants of the MPX [21]
   Switzerland Geneva Police [22]

References edit

  1. ^ Wilk, Remigiusz. "SIG Sauer: The Academy. Visit to New Hampshire". Milmag.
  2. ^ a b Ayoob, Massad (14 May 2014). Gun Digest Book of SIG-Sauer. Iola, Wisconsin: F+W Media. ISBN 978-1-4402-3920-5.
  3. ^ a b Staff (14 January 2016). "SIG Sauer Announces MPX 9 mm Semi-automatic Carbine". by American Rifleman.
  4. ^ Staff (11 April 2015). "Long-Awaited SIG MPX in 9 mm Now Shipping". by American Rifleman.
  5. ^ a b Harrison, Iain (2015). "SIG SAUER MPX – Next-Gen Sub Gun". Recoil. 3 (21).
  6. ^ MPX, SIG. "SIG MPX Brochure (PDF)" (PDF).
  7. ^ "Modern Firearms - SIG-Sauer MPX submachine gun (USA)". modernfirearms.net. 13 May 2013. Retrieved 27 August 2017.
  8. ^ Mann, Richard Allen; Lee, Jerry (20 November 2013). The Gun Digest Book of Modern Gun Values: The Shooter's Guide to Guns 1900-Present. Iola, Wisconsin: F+W Media. p. 206. ISBN 978-1-4402-3752-2.
  9. ^ Sweeney, Patrick (18 January 2016). Gun Digest Book of Suppressors. Iola, Wisconsin. p. 139. ISBN 978-1-4402-4532-9. {{cite book}}: |work= ignored (help)CS1 maint: location missing publisher (link)
  10. ^ Crane, David (24 May 2014). "SIG SAUER MPX KeyMod Multi-Cal Machine Pistol/Mini Submachine Gun (SMG)/PDW (Personal Defense Weapon) with Silencer/Sound Suppressor at NDIA SOFIC 2014, its also found in the upcoming video game "Targeted Enemy" as the slightly opticly modified "MP 10 9mm"". Defense Review.
  11. ^ The Rise And Fall Of The SB-15 ‘Sig Brace’ Grand View Outdoors. March 24, 2015.
  12. ^ "Breaking News Update: ATF Reversal Letter To SB Tactical -". The Firearm Blog. 24 April 2017. Retrieved 10 October 2021.
  13. ^ "SIG MPX K". www.sigsauer.com.
  14. ^ "ATF Rules Against SIG MPX", The Outdoor Wire, 14 April 2014
  15. ^ "Judge favors ATF in Sig lawsuit: It's a silencer", Guns.com, 25 September 2015
  16. ^ "警察鐵路應變部隊下周日起執勤 背囊藏最新MPX衝鋒槍巡高危車站".
  17. ^ "Nation Security Guard(NSG) of India in Pictures - Defence View". 20 May 2021.
  18. ^ "SIG MPX: Pilihan Baru Submachine Gun Satuan Elite TNI Dan Polri". indomiliter.com (in Indonesian). 2 November 2016. Retrieved 4 March 2021.
  19. ^ "Sig MPX for Malaysian Army Special Forces - Asian Defence Journal". 20 February 2023.
  20. ^ "KomChadLuek 7 Jan 2018". 7 January 2018.
  21. ^ Staff (2 January 2019). "U.S. Army Contracting Command issues award to SIG SAUER". Military Times. Retrieved 23 December 2021.
  22. ^ "Nouveau matos de la police: c'est du lourd!" (in French). 2 April 2019.

External links edit

  • SIG MPX Brochure