From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

CIS 50 HMG.jpg
The CIS 50MG on display during Singapore Army open house 2007.
TypeHeavy machine gun
Place of originSingapore
Service history
In service1991–present[1]
Used bySee Users
Production history
DesignerChartered Industries of Singapore (CIS, now ST Kinetics)[1][2]
Manufacturer• CIS: 1988–2000[1]
• ST Kinetics: 2000–present[1]
Mass30 kg (66.14 lb) (complete gun assembly w/o feed chute and tripod adaptor)[1][3]
Length1,778 mm (70.0 in) with stock[1]
Barrel length1,143 mm (45.0 in)[1]
Width190 mm (7.5 in)[3]

Cartridge12.7×99mm NATO[3]
BarrelsSingle barrel (progressive RH parabolic twist, 8 grooves)[1]
ActionGas-operated, rotating bolt[1]
Rate of fire400–600 rounds/min[1]
Muzzle velocity890 m/s (2,920 ft/s)[1]
Feed systemSingle sprocket Belt-fed with dual-feed chutes[1]
SightsFolding leaf sight[1]

The STK 50 MG, formerly known as the CIS 50MG,[a] is a gas-operated, air-cooled, belt-fed heavy machine gun developed and manufactured by Chartered Industries of Singapore (CIS, now ST Kinetics) in the late 1980s, in response to a request by the Singaporean Defence Ministry to replace the 12.7mm Browning M2HB machine guns then in ubiquitous service with the Singapore Armed Forces (SAF).[2][4]

The aim was to have a brand new heavy machine gun design, that fires the same type of .50 cal rounds as the M2HB machine guns and to have the gun parts more readily available in view of easing SAF's chain of logistics and supplies.[1]


Close in defence aboard RSS Resilience

The CIS engineers learnt from the lesson of the canceled (lack of funding) American "Dover Devil GPHMG" program known as the Special Projects Group at Picatinny Arsenal led by Charles J. Rhoades. Curt Johnson and Phil Baker developed the original concept to create a modular weapon suited for modern tactical doctrines and production techniques.[3] In 1988, CIS introduced the new 12.7mm machine gun which was aptly named as the CIS 50MG, after two years of development and testing phase.[2]

As the STK 50 MG is a gas-operated, air-cooled, belt-fed weapon, the gun is operated using dual gas pistons, located in two gas tubes placed on either side of the barrel. The barrel is locked by means of a rotary bolt with multiple radial lugs that engages the barrel extension, eliminating the need for headspace adjustments. The CIS 50MG utilises the same "constant recoil" system used in the Ultimax 100 and it also has a quick-detachable barrel equipped with a carrying handle to facilitate the ease of barrel changing under combat situations or during operational manoeuvres.[2]


The one unique feature of the weapon is its dual belt-feed system, the system allows for fast and easy switching of ammunition from standard ball rounds to the Raufoss Mk 211 Armor-Piercing-Incendiary rounds or the Saboted light armor penetrator (SLAP), which are capable of penetrating a rolled homogeneous armour plate with a thickness of 25 mm (0.98 in) from a range of 1 km (0.62 mi).[2][3]

Such systems are more commonly used in modern automatic cannons such as the M242 Bushmaster 25mm cannon and the Mk44 Bushmaster II 30mm cannon, both of which are also in use by the Singapore Army's Bionix AFVs.[1]



  1. ^ Using the Wayback machine on this CIS 50 page indicates that the CIS 50 MG name was used until 2016, when it changed to the STK 50 MG name as seen here.


  1. ^ a b c d e f g h i j k l m n o p q r s t Richard J, 2008.
  2. ^ a b c d e "50MG Product Brochure" (PDF). ST Engineering. Archived from the original (PDF) on 19 February 2009. Retrieved 11 September 2008.
  3. ^ a b c d e Andrew C, 1989.
  4. ^ "Maximum Firepower: The Machine Guns of the SAF". Singaporean Defence Ministry. 7 June 2008. Archived from the original on 4 August 2012. Retrieved 14 July 2010.
  5. ^ "STK 50MG". Retrieved 27 November 2019.
  6. ^ "Un repaso a las armas ligeras de Pindad" (in Spanish). ARMAS. Archived from the original on 2 April 2013. Retrieved 5 July 2010.
  7. ^ "STK 50MG Heavy Machine Gun |".
  8. ^ Gbadamosi, Adesanya (7 June 2015). "Photos: Nigerian Made Drone And Gunboats On Display[Must See]".
  9. ^ Binnie, Jeremy; de Cherisey, Erwan (2017). "New-model African armies" (PDF). Jane's. Archived from the original (PDF) on 22 June 2017.
  10. ^ Muhammad Juffry, Bin Joihani (July–August 2009). "PCG upgrades with new fleet and training centre". Police Life Monthly. Singapore: Singapore Police Force. 35 (7). ISSN 0217-8699. Archived from the original on 22 June 2011. Retrieved 10 November 2010.

External links[edit]