The Mk44 Bushmaster II is a 30 mm

chain gun A chain gun is a type of autocannon or machine gun that uses an external source of power to cycle the weapon's action via a continuous loop of chain, similar to that used on a motorcycle or bicycle, instead of diverting excess energy from the ...

manufactured by

Northrop Grumman Northrop Grumman Corporation is an American multinational Aerospace manufacturer, aerospace and Arms industry, defense company. With 97,000 employees and an annual revenue in excess of $40 billion, it is one of the world's largest Arms industry ...

. It is a derivative of the 25 mm

M242 Bushmaster The M242 Bushmaster chain gun is a 25 mm caliber, 25 mm (25×137mm) single-barrel chain-driven autocannon. It is used extensively by the United States Armed Forces, U.S. military, such as in the Bradley fighting vehicle, as well as by other NAT ...

, and uses 70% of the same parts as the M242 while increasing the firepower by as much as 50% with the 20% increase in caliber size. The barrel is chromium-plated for extended life. The gun uses standard

GAU-8 Avenger The General Electric GAU-8/A Avenger is a 30 mm hydraulically driven seven-barrel Gatling-style autocannon that is primarily mounted in the United States Air Force's Fairchild Republic A-10 Thunderbolt II. Designed to destroy a wide variety of ...

ammunition that is available in API (Armor-Piercing Incendiary), HEI (High-Explosive Incendiary) and APFSDS-T (Armor-Piercing Fin-Stabilized Discarding Sabot-Tracer) variants. The gun can be converted to a caliber of 40×180 mm, which involves changing the barrel and a few key parts, to use the SuperShot 40 cartridge. It can also be converted to use the 30×170 mm RARDEN cartridge.

History

The Bushmaster II is the standard primary armament of the Bionix-II AFV currently in service with the

Singapore Army The Singapore Army is the Ground warfare, land Military branch, service branch of the Singapore Armed Forces (SAF). The largest of the Singapore Armed Forces#Organisation, four branches of the SAF, the Singapore Army traces its origins to the Inf ...

, the

KTO Rosomak The KTO Rosomak () is a family of eight-wheeled armored fighting vehicles derived from the Finnish Patria AMV. It is produced by Rosomak S.A., a Polish Armaments Group company, in Siemianowice Śląskie. History The XC-360 transporter was ...

in Polish service, and the CV90 AFVs in Finnish, Norwegian and

Swiss Swiss most commonly refers to: * the adjectival form of Switzerland * Swiss people Swiss may also refer to: Places * Swiss, Missouri * Swiss, North Carolina * Swiss, West Virginia * Swiss, Wisconsin Other uses * Swiss Café, an old café located ...

service. Although the

United States Air Force The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...

selected this cannon to replace the 25 mm GAU-12 Equalizer and

Bofors 40 mm Automatic Gun L/60 The Bofors 40 mm Automatic Gun L/60 (often referred to simply as the "Bofors 40 mm gun", the "Bofors gun" and the like, see #Name, name) is an Anti-aircraft warfare, anti-aircraft autocannon, designed in the 1930s by the Swedish arms ...

guns on its fleet of AC-130U gunships in 2007, this plan was later canceled. The

United States Marine Corps The United States Marine Corps (USMC), also referred to as the United States Marines or simply the Marines, is the maritime land force service branch of the United States Department of Defense. It is responsible for conducting expeditionar ...

' cancelled Expeditionary Fighting Vehicle, was expected to be armed with this cannon as well. Some

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

vessels, such as the new

amphibious transport dock An amphibious transport dock, also called a landing platform dock (LPD), is an amphibious warfare ship, a warship that embarks, transports, and lands elements of a landing force for expeditionary warfare missions. Several navies currently oper ...

are armed with the Bushmaster II for surface threat defense. The Bushmaster II cannon is used in the DS30M Mark 2 Automated Small Calibre Gun (ASCG) point defense system that is fitted to the

Royal Navy The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...

Type 23 frigate The Type 23 frigate or Duke class is a class of frigates built for the United Kingdom's Royal Navy. The ships are named after British Dukes, thus leading to the class being commonly known as the Duke class. The first Type 23, , was commission ...

s. The Bushmaster II cannon is also used in the Turkish made Aselsan SMASH stabilized weapon station. The USAF had experimented with installing Bushmaster II cannons on their AC-130U gunships in place of the GAU-12 and Bofors 40 mm cannons. On 11 August 2008, the effort was canceled because of problems with the Bushmaster's accuracy in tests "at the altitude we were employing it." There were also schedule considerations that drove the decision. On 9 July 2012, the Air Force type classified a new version of the Bushmaster called the GAU-23/A. The cannon will be used on the AC-130W and the AC-130J gunships. The

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Department of Defense. It is the world's most powerful navy with the largest displacement, at 4.5 million tons in 2021. It has the world's largest aircraft ...

uses the Mk44 Bushmaster II in the Mk 46 Mod 2 Gun Weapon System (GWS). The GWS is produced by

General Dynamics General Dynamics Corporation (GD) is an American publicly traded aerospace and defense corporation headquartered in Reston, Virginia. As of 2020, it was the fifth largest defense contractor in the world by arms sales and fifth largest in the Unit ...

to give warships protection against small, high-speed surface craft. A Mk 46 turret consists of the 30 mm chain gun, a

forward looking infrared Forward-looking infrared (FLIR) cameras, typically used on military and civilian aircraft, use a thermographic camera that senses infrared radiation. The sensors installed in forward-looking infrared cameras, as well as those of other thermal ...

(FLIR) sensor, a low light television camera, and a

laser rangefinder A laser rangefinder, also known as a laser telemeter or laser distance meter, is a rangefinder that uses a laser beam to determine the distance to an object. The most common form of laser rangefinder operates on the time of flight principle by ...

. The guns fire at 200 rounds per minute and are fed by a 400-round magazine through 200-round dual feeds. Effective range is for full-caliber high-explosive or armor-piercing ammunition, which can be extended when using sub-caliber rounds. The Mk 46 GWS is permanently installed on the ''San Antonio''-class amphibious transport dock and can be installed on and s as part of the surface warfare (SuW) package. In 2012, the Navy decided to replace the Mk 110 57 mm cannons on s with the Mk 46 GWS.

Orbital ATK Orbital ATK Inc. was an American aerospace manufacturer and defense industry company. It was formed in February 9, 2015 from the merger of Orbital Sciences Corporation and parts of Alliant Techsystems (ATK). Orbital ATK designed, built, and de ...

developed a modified version of the Bushmaster II, known as the Mk44 STRETCH, which can fire the 30x173 mm Mk310 PABM-T airburst round. In January 2020,

revealed the development of proximity

airburst An air burst or airburst is the detonation of an explosive device such as an anti-personnel artillery shell or a nuclear weapon in the air instead of on contact with the ground or target. The principal military advantage of an air burst over ...

rounds for the LCS' 30 mm gun modules to destroy small

unmanned aerial vehicle An unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS), commonly known as a drone, is an aircraft with no human pilot, crew, or passengers onboard, but rather is controlled remotely or is autonomous.De Gruyter Handbook of Dron ...

s (UAVs). Since the modules feature dual feeders, different types of rounds could be fed for different targets. In October 2023, the UK announced it would be delivering the Terrahawk Paladin to Ukraine as part of assistance during the

Russian invasion of Ukraine On 24 February 2022, , starting the largest and deadliest war in Europe since World War II, in a major escalation of the Russo-Ukrainian War, conflict between the two countries which began in 2014. The fighting has caused hundreds of thou ...

. The Terrahawk Paladin is made by MSI Defence Systems (MSI-DS) as a land-based version of the Seahawk. It is a static Very Short-Range Air Defense (VSHORAD) Counter Unmanned Aerial Systems (C-UAS) system that can be deployed off a truck. The system combines radars, EO/IR cameras, and laser rangefinders with a 30 mm Mk44 Bushmaster II chain gun with 240 rounds of airburst munitions capable of engaging small UAS out to .

XM813

The XM813 Bushmaster is based on the Mk44 and is offered as an upgrade for

U.S. Army The United States Army (USA) is the primary land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United Stat ...

M1126 Stryker and

M2 Bradley The M2 Bradley, or Bradley IFV, is an American infantry fighting vehicle that is a member of the Bradley Fighting Vehicle family. It is manufactured by BAE Systems Land & Armaments (formerly United Defense) and entered service in 1981, with fi ...

vehicles, as well as having been a contender to be the primary armament of the

Ground Combat Vehicle The Ground Combat Vehicle (GCV) was a program initiated by the United States Army in 2009, with the goal of developing a next-generation armored fighting vehicle. The first variant of the GCV to be developed would be an infantry fighting vehicle ...

. The improvements include a longer barrel, integral mount to increase first round hit probability by up to 10%, a dual recoil system to enhance accuracy to help cope with future hotter propellants, and a Meggitt linkless dual feed ammunition system. The 30 mm chain gun can fire Mk310 Programmable

Air Burst An air burst or airburst is the detonation of an explosive device such as an anti-personnel artillery shell or a nuclear weapon in the air instead of on contact with the ground or target. The principal military advantage of an air burst over ...

Munition rounds to attack targets in

defilade Enfilade and defilade are concepts in military tactics used to describe a military formation's exposure to enemy fire. A formation or position is "in enfilade" if weapon fire can be directed along its longest axis. A unit or position is "in de ...

. The

United States Army Research, Development and Engineering Command The Combat Capabilities Development Command, (DEVCOM, aka CCDC) (formerly the United States Army Research, Development, and Engineering Command (RDECOM)) is a subordinate command of the U.S. Army Futures Command. RDECOM was tasked with "creatin ...

helped enhance the XM813 mainly for safety and turret integration. By changing five parts, the gun caliber can be increased to 40 mm. As of November 2013, the XM813 was being tested at

Aberdeen Proving Ground Aberdeen Proving Ground (APG) is a U.S. Army facility located adjacent to Aberdeen, Harford County, Maryland, United States. More than 7,500 civilians and 5,000 military personnel work at APG. There are 11 major commands among the tenant units, ...

over three months to ensure reliability levels of 40,000 mean rounds between failures. Long-term plans are to equip vehicles with the Bushmaster III 35mm/50mm cannon. The XM813 was demonstrated in September 2014 at the ARDEC Digital Multi-Purpose Range Complex. The gun was mounted on a

Bradley Fighting Vehicle The Bradley Fighting Vehicle (BFV) is an American continuous track, tracked armored fighting vehicle of the United States developed by FMC Corporation and now manufactured by BAE Systems Land & Armaments, formerly United Defense. It is named for ...

and fired at targets up to away. An enhanced fire control system improves long-range accuracy to kill targets with fewer bursts, sometimes as few as two or three rounds instead of 10. The XM813 30 mm cannon is intended to replace the

25 mm chain gun, and can be mounted on vehicles other than the Bradley. Two capabilities not demonstrated were its linkless ammunition with airburst capabilities; airburst rounds increase lethality by enabling engagement of targets in defilade when they would otherwise only be suppressed by fire. In early 2015, the U.S. Army approved an upgrade for 81

Stryker The Stryker is a family of Eight-wheel drive, eight-wheeled armored fighting vehicles derived from the Canadian LAV III. Stryker vehicles are produced by General Dynamics Land Systems-Canada (GDLS-C) for the United States Army in a plant in L ...

vehicles of a

Stryker Brigade Combat Team The brigade combat team (BCT) is the basic Military deployment, deployable Military unit, unit of maneuver in the United States Army, U.S. Army. A brigade combat team consists of one combat arms branch maneuver Brigade (United States Army), b ...

deployed in Europe to be upgunned with the Mk44 30 mm Bushmaster cannon to increase their lethality against other light armored vehicles used by Russia in the theater. The cannons will be installed by 2018, and may be the first step in adding the Bushmaster to the entire active fleet of about 1,000 Strykers; the XM813 variant will be used with the Strykers. The XM813 has a demonstrated firing ability out to for precision firing, nearly twice as far as the M2 12.7 mm caliber machine gun that has a maximum effective range of as an area suppression weapon. The first upgunned Stryker, known as the "Dragoon" for the 2nd Cavalry Regiment the vehicles will be part of, was delivered in October 2016, and the first Infantry Carrier Vehicle - Dragoon (ICVD) was delivered to the 2CR in Germany in December 2017. The ATK MK44-ABM variant of the Bushmaster was selected in 2018 by the

Spanish Army The Spanish Army () is the terrestrial army of the Spanish Armed Forces responsible for land-based military operations. It is one of the oldest Standing army, active armies – dating back to the late 15th century. The Spanish Army has existed ...

to equip the Tizona turret of the Line version (IFV) of the Dragón IFV, the replacement of the Pegaso BMR.

Users

30 mm cannons

Navy A navy, naval force, military maritime fleet, war navy, or maritime force is the military branch, branch of a nation's armed forces principally designated for naval warfare, naval and amphibious warfare; namely, lake-borne, riverine, littoral z ...

: *

Army An army, ground force or land force is an armed force that fights primarily on land. In the broadest sense, it is the land-based military branch, service branch or armed service of a nation or country. It may also include aviation assets by ...

: AS21 Redback (EOS T-2000 turret) *

: Piranha IIIC DF30 *

: Mowag Piranha IIIC *

: VBTP-MR Guarani *

: , NAM ''Atlântico'' aircraft carrier *

: XM1296

Dragoon *

Patria AMV The Patria AMV (Armoured Modular Vehicle) is an Eight-wheel drive, 8×8 multi-role list of military vehicles, military vehicle produced by the Finland, Finnish defence industry company Patria (company), Patria. The main feature of the AMV is its ...

(Elbit UT30 Mk2 turret) *

: Pandur II CZ, CV9030CZ *

: CV9030FIN *

: Sentinel II 8×8, Sentinel II 6×6 (with Elbit UT30 turret) *

: Pindad Cobra IFV (

ARES Ares (; , ''Árēs'' ) is the List of Greek deities, Greek god of war god, war and courage. He is one of the Twelve Olympians, and the son of Zeus and Hera. The Greeks were ambivalent towards him. He embodies the physical valor necessary for ...

UT30 MK2 turret) *

: ''Mamuju''-class, ''Pari''-class patrol vessel, ''Pollux''-class research vessel and ''Clurit''-class fast attack craft *

Coast Guard A coast guard or coastguard is a Maritime Security Regimes, maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with cust ...

: ''Tanjung Datu''-class patrol vessel, ''Pulau Nipah''-class patrol vessel and ''Bintang Laut''-class patrol vessel *

: s, s (later ships), & s * Common tactical wheeled vehicle: ** ** *

: ''Swiftships'' patrol boats *

: Mowag Piranha IIIH *

: Freccia EVO (Combat and Reconnaissance variants) *

Vilkas Vilkas is a Lithuanian language family name In many societies, a surname, family name, or last name is the mostly hereditary portion of one's personal name that indicates one's family. It is typically combined with a given name to form t ...

(Orbital ATK Mk44S variant) * Malaysian Navy: ''Maharaja Lela''-class frigate *

: and *

: CV9030N *

: s *

: s and Shaldag Mk.V missile fast attack craft *

: Rosomak (

Hitfist Oto Melara Hitfist is a two-man turret for armored vehicles developed by the Italian Oto Melara company. The turrets are designed to mount a 25mm Oerlikon KBA or 30/40mm ATK Mk44 Bushmaster II autocannon. The main armament may mount a co-axia ...

and

ZSSW-30 The ZSSW-30 (Polish language, Polish: Zdalnie Sterowany System Wieżowy 30 mm - 30mm Remote Control Turret System) is a Polish Remote controlled weapon station, remotely controlled turret designed by Huta Stalowa Wola and WB Group, WB Electronics ...

Borsuk Borsuk (the word for "badger" in a number of Slavic languages) may refer to: *Angela Borsuk (born 1967), Israeli chess player *Karol Borsuk, Polish mathematician *Pavlo Borsuk, Ukrainian canoeist *Borsuk, Hrubieszów County in Lublin Voivodeship (e ...

, CBWP Heavy IFV * Army:

Mowag Piranha V The Piranha V infantry fighting vehicle (IFV) is the fifth generation variant of the Mowag Piranha family of vehicles. It was designed by General Dynamics European Land Systems - Mowag GmbH. The first prototype was completed in 2008. It was fir ...

National Guard National guard is the name used by a wide variety of current and historical uniformed organizations in different countries. The original National Guard was formed during the French Revolution around a cadre of defectors from the French Guards. ...

: LAV-700 IFV (CMCT turret) *

: Bionix II, Hunter AFV *

: Piranha V - Dragon (219 VCR, 14 VCR-PC, 58 VEC) *

: CV9030CH *

: CM-34 (IFV variant) *

Military police Military police (MP) are law enforcement agencies connected with, or part of, the military of a state. Not to be confused with civilian police, who are legally part of the civilian populace. In wartime operations, the military police may supp ...

: CM-34 (IFV variant) *

: ''Tachin''-class frigate, , ''Krabi''-class offshore patrol vessel, ''Leamsing''-class patrol craft (gun), coastal patrol craft, ''T.994''-class coastal patrol craft, ''Angthong''-class amphibious transport dock and ''Ladya''-class mine countermeasure vessel *

: XM1296

Dragoon,

( Hitfist-30P) *

: ''River-class Batch II'' offshore patrol vessels, ''Type 23'' frigate, ''Type 45'' destroyer *

: XM1296

Dragoon *

USMC The United States Marine Corps (USMC), also referred to as the United States Marines or simply the Marines, is the maritime land force service branch of the United States Department of Defense. It is responsible for conducting expeditionary ...

: ACV (Iveco SuperAV with Kongsberg MCT-30 turret) *

: transport ship,

Littoral combat ship A littoral combat ship (LCS) is either of two classes of relatively small surface vessels designed for littoral warfare in near-shore operations by the United States Navy. It was "envisioned to be a networked, agile, stealthy surface comba ...

and *

Air Force An air force in the broadest sense is the national military branch that primarily conducts aerial warfare. More specifically, it is the branch of a nation's armed services that is responsible for aerial warfare as distinct from an army aviati ...

: AC-130W, AC-130J (GAU-23/A) *

: Polar Security Cutter

Munitions

References

* http://www.atk.com/Products/documents/108279_01_Mk44.pdf ; Notes

External links

Alliant Techsystems (ATK) Mk44 Bushmaster Automatic Cannon Fact Sheet

Alliant Techsystems (ATK) GAU-23 Bushmaster Automatic Cannon Fact Sheet

{{Alliant Techsystems 30 mm artillery Autocannon Chain guns Vehicle-mounted weapons United States Marine Corps equipment Alliant Techsystems Military equipment introduced in the 2000s

History

XM813

Users

30 mm cannons

Munitions

See also

References

External links