Artillery

M777

Also known as
  • M-777
  • M777A2
  • LW155
  • Ultralightweight Field Howitzer
  • M777 Ultralightweight Field Howitzer

The M777 is a lightweight British-American 155 mm towed howitzer built by BAE Systems for mobile artillery units. Its titanium-and-aluminum structure, hydraulic mechanisms, and digital fire-control system made it a lighter successor to the M198 while keeping NATO 155 mm ammunition compatibility, including Excalibur precision fires documented in Afghanistan, Syria, Iraq, and Ukraine-related service.

M777, 155 mm towed howitzer, Artillery
Image source: M777 Light Towed Howitzer image

Role in Conflicts

Ukraine Donor Context

The M777 became one of the earliest Western 155 mm artillery systems publicly transferred to Ukraine after Russia's full-scale 2022 invasion, with official sources documenting U.S., Canadian, and Australian deliveries or shipment plans in April and May 2022.

United States

The Pentagon announced 72 M777 howitzers, 144,000 artillery rounds, and towing vehicles in an April 2022 Ukraine security-assistance package.

Canada

Canada said it had delivered a number of M777 howitzers and associated ammunition to Ukraine's security forces alongside U.S. support.

Australia

Australian Defence reported that six M777 howitzers with ammunition had been gifted to Ukraine and that M777s were loaded for Europe from RAAF Base Amberley.

Sources: Austin to Host Meeting in Germany to Discuss Ukraine's Long-Term Defense Needs; Canada announces artillery and other additional military aid for Ukraine; Working together for Ukraine.

Profile / Specs

Profile

Origin
United States / United Kingdom
Built by
BAE Systems
Type
155 mm towed howitzer
Service note
Modern NATO artillery
Unit cost
FY2025 Army M777 Mods gross/weapon-system unit cost: $450,476 (budget modernization line, not a complete howitzer procurement price)
Produced
First introduced into U.S. Marine Corps service in 2005
Number built
1,071 guns in the U.S.-UK production program by 2011; BAE reported more than 1,250 M777s in service by 2025

Specifications

Crew
About 7
Caliber
155 mm / 39 caliber
Weight
Less than 4,200 kg / 9,300 lb
Length
10.7 m deployed; 9.5 m towed
Range
24.7 km unassisted; about 30 km rocket-assisted; more than 40 km with Excalibur
Mobility
Towed; light enough for helicopter and cargo-aircraft lift
Rate of fire
Up to about 5 rounds/min maximum; about 2 rounds/min sustained
What Makes It Distinct

BAE and Army budget sources describe the M777 as a weight-saving 155 mm system built to move quickly, emplace fast, and stay useful as precision artillery requirements changed.

FeatureSource-backed detail
StructureBAE says the LW155 uses titanium and aluminum alloys, with major titanium structures and hydraulics for the breech, load tray, recoil, and wheel arms.
Weight savingsBAE describes the gun as less than 4,200 kg and about half the weight of conventional towed 155 mm systems, while the Army budget book says it saves 7,000 pounds versus the M198.
Program scaleBAE said the U.S.-UK production program had reached 1,071 guns by 2011 as the Army began equipping Infantry Brigade Combat Teams.
ModernizationThe Army budget book says current M777 funding supports digital fire-control hardware and software, including Software Defined Radios, mission computers, chief-of-section display, and APNT/M-Code upgrades.

Sources: U.S. Upgrades and Orders More Lightweight BAE Systems Howitzers; M777 Mods Army budget justification.

Variants

The M777 family is commonly described through its lightweight LW155 program name, digital-fire-control variants, and experimental extended-range work.

VariantConfigurationDesignation notes
LW155Lightweight 155 mm program designation

BAE and Army budget sources describe the M777 as the lightweight 155 mm howitzer program that replaced the heavier M198 while retaining NATO 155 mm ammunition compatibility.

Sources: U.S. Upgrades and Orders More Lightweight BAE Systems Howitzers, M777 Mods Army budget justification

M777A1Digital fire-control variant

Army Technology identifies the M777A1 as a variant with digital fire-control equipment.

Sources: M777 Ultralightweight Field Howitzer

M777A2Excalibur-compatible digital variant

The Army budget justification says the M777A2 can program and fire Excalibur guided projectiles to more than 40 km with sub-10-meter CEP accuracy.

Sources: M777 Mods Army budget justification

M777ERExtended-range demonstrator

U.S. Army articles describe the M777ER as an M777A2 extended-range test path using a 55-caliber tube manufactured at Watervliet Arsenal, with Yuma firing tests and a 70 km demonstration goal rather than a fielded combat variant.

Sources: Picatinny engineers seek to double range of modified howitzer, Picatinny engineers double range with modified M777A2 Extended Range howitzer

Air Transport

The M777's lightweight towed design supports air movement by heavy-lift helicopter and tactical aircraft.

CarrierCarrier typeCarriage evidence
CH-53K King Stallion, Heavy-lift transport helicopter, Aircraft & UAVsCH-53K King StallionHeavy-lift transport helicopter

A DVIDS caption says a CH-53K King Stallion transported an M777 towed 155 mm howitzer during Exercise Northern Strike 24.

Sources: U.S. Marines with HMH-461 conduct M777 towed 155 mm howitzer transport during Exercise Northern Strike 24

CH-47 Chinook helicopter, Heavy-lift transport helicopter, Aircraft & UAVsCH-47 Chinook helicopterHeavy-lift transport helicopter

The Australian Army says the M777 can be lifted by the Army CH-47 Chinook helicopter, alongside airlift by C-17A and C-130J aircraft.

Sources: M777 155mm lightweight towed howitzer

C-130 Hercules, Tactical airlift transport aircraft, Aircraft & UAVsC-130 HerculesTactical airlift aircraft

The Australian Army says the M777 can be transported by C-130J aircraft, alongside C-17A airlift and CH-47 helicopter lift.

Sources: M777 155mm lightweight towed howitzer

Towing Vehicles

The M777 is a towed system; sources document both general gun-tractor use and U.S. Army M1083 Medium Tactical Vehicle towing.

Compatible itemItem typeCompatibility evidence
M1083 6x6 medium tactical vehicle, 5-ton 6x6 medium tactical cargo truck, Support EquipmentM1083 6x6 medium tactical vehicle6x6 medium tactical truck

A 2d Cavalry Regiment DVIDS story says M777A2 crews currently towed the howitzer with an M1083 Medium Tactical Vehicle while evaluating a Stryker prime-mover concept.

Sources: 2CR discusses Stryker modification for howitzer crews

Ammunition Fired

The M777's long-range tube and digital fire-control system let it fire standard NATO 155 mm ammunition and precision projectiles.

AmmunitionAmmunition typeFiring evidence
M795 155 mm high-explosive projectile, 155 mm high-explosive projectile, MunitionsM795 155 mm high-explosive projectile155 mm high-explosive projectile

GICHD's Ukraine ordnance guide says the M795 is typically employed with M777 howitzers and is compatible with NATO 155 mm artillery under STANAG-4425.

Sources: GICHD Explosive Ordnance Guide for Ukraine

M549A1 rocket-assisted projectile, 155 mm high-explosive rocket-assisted projectile, MunitionsM549A1 rocket-assisted projectile155 mm rocket-assisted projectile

GICHD's Ukraine ordnance guide says M549-family rocket-assisted projectiles may be used with M777 howitzers, M109 self-propelled howitzers, and other NATO-compliant 155 mm ordnance.

Sources: GICHD Explosive Ordnance Guide for Ukraine

M982 Excalibur guided artillery projectile, 155 mm GPS/INS-guided artillery projectile, MunitionsM982 Excalibur guided artillery projectile155 mm guided projectile

The Army budget justification says the M777A2 can program and fire Excalibur to ranges in excess of 40 km with better than 10-meter CEP accuracy.

Sources: M777 Mods Army budget justification

Precision reach

The same Army budget book lists 24.7 km unassisted range and about 30 km with rocket-assisted projectiles, showing how the gun's reach expands with ammunition choice.

Sources: M777 Mods Army budget justification

Ammunition And Cost Context

The M777 can fire standard 155 mm rounds, rocket-assisted rounds, and precision Excalibur projectiles. The Army budget line used here concerns M777 modifications and modernization, while Excalibur contract data gives a separate reference point for the precision round.

ItemContext
M777 Mods lineFY2025 Army budget justification lists a gross/weapon-system unit cost of 450.476 thousand dollars for the M777 Mods procurement line, not a complete new howitzer price.
Excalibur roundRaytheon said the U.S. Army awarded a $31.8 million contract for 464 Excalibur Ib projectiles, or about $68,500 per round.
Precision effectThe Army budget book says Excalibur extends the M777A2 to more than 40 km with better than 10-meter CEP accuracy.

Sources: M777 Mods Army budget justification; US Army awards Raytheon $31.8 million contract for continued Excalibur production.

Timeline

M777 Key Events

  1. First Marine Corps fielding

    Headquarters Marine Corps reported that 3rd Battalion, 11th Marine Regiment received three new M-777 Lightweight Howitzers and fired them in the Combat Center desert during the weapon's debut.

    Sources: New howitzer makes thunderous debut

  2. First Camp Pendleton firing

    Camp Pendleton reported 2nd Battalion, 11th Marine Regiment firing the M777 for the first time at the base while gearing up for Iraq with the newly fielded weapon.

    Sources: Howitzer booms at Pendleton

  3. Iraq combat firing documented

    A Marine Corps Times caption identifies Marines from Sierra Battery, 5th Battalion, 10th Marine Regiment firing a high-explosive round from an M777A2 at Camp Fallujah in Iraq.

    Sources: Marines test 3 big guns in week-long artillery experiment

  4. Excalibur record-range firing in Afghanistan

    Raytheon reported that U.S. Marines in Helmand province fired an Excalibur projectile from an M777 howitzer at record range in Afghanistan.

    Sources: US Marines fire Excalibur from record range in Afghanistan

  5. M777ER range demonstrator described

    The U.S. Army reported Picatinny engineers modifying an M777A2 into the M777ER demonstrator with a longer cannon tube for extended-range testing.

    Sources: Picatinny engineers seek to double range of modified howitzer

  6. Ukraine support package announced

    The Pentagon announced that 72 M777 155 mm howitzers would go to Ukraine as part of a new security assistance package, alongside 144,000 artillery rounds and towing vehicles.

    Sources: Austin to Host Meeting in Germany to Discuss Ukraine's Long-Term Defense Needs

  7. Canada delivers M777s to Ukraine

    Canada announced that it had delivered a number of M777 howitzers and associated ammunition to Ukraine's security forces in conjunction with U.S. support.

    Sources: Canada announces artillery and other additional military aid for Ukraine

  8. Australian M777s airlifted for Ukraine

    Australian Defence reported an airlift from RAAF Base Amberley carrying M777 howitzers and Bushmaster vehicles for Ukraine after Australia gifted six M777s with ammunition.

    Sources: Working together for Ukraine

  9. New M777 structures contract

    BAE Systems announced a $162 million U.S. Army contract for new M777 lightweight howitzer major structures, with the first structures to be produced at Sheffield and within the U.S. supply chain.

    Sources: U.S. Army awards BAE Systems $162 million contract for new M777 structures

  10. Second-source M776 cannon production

    BAE Systems announced a $146 million contract to begin manufacturing M776 cannons for the U.S. Army's M777 howitzer at Louisville, Kentucky.

    Sources: BAE Systems awarded $146 million for M776 cannon production

Media

M777 Videos

M777 Images

M777, 155 mm towed howitzer, Artillery - view 1
Source: 3rd Cavalry Regiment M777 howitzer image
M777, 155 mm towed howitzer, Artillery - view 2
Source: U.S. Army M777 howitzer image
Related Weapon Systems
M119, 105 mm lightweight towed howitzer, ArtilleryArtilleryM119105 mm lightweight towed howitzerThe M119 is the U.S. 105 mm lightweight towed howitzer derived from the British L119 light gun and built around air-mobile infantry fire support. The M119A3 variant adds digital fire control, self-location, and communications upgrades while retaining a light carriage that can be moved by trucks, cargo aircraft, or helicopter. U.S. Army sources place the type in Gulf War, Iraq War, and Afghanistan service, and Ukrainian forces later received American 105 mm howitzers during the 2014 Russia-Ukraine War.
M198 155 mm howitzer, 155 mm towed howitzer, ArtilleryArtilleryM198 155 mm howitzer155 mm towed howitzerThe M198 is a U.S.-designed 155 mm towed howitzer developed at Rock Island Arsenal to replace older M114-series guns. Its split-trail carriage, nine-person crew, air-transportable layout, and 22-30 km range made it a standard U.S. Army and Marine Corps fire-support weapon before the lighter M777 replaced it in U.S. service. Direct conflict sourcing now traces M198 fielding from Desert Storm through U.S. use in Afghanistan and Iraq, Islamic State capture and cross-border use in Iraq and Syria, Iraq-aligned militia firing, and coalition-backed Iraqi Army live-fire training.
155 mm artillery round, 155 mm artillery ammunition family, MunitionsMunitions155 mm artillery round155 mm artillery ammunition familyThe 155 mm artillery round is a family-level label for complete 155 mm howitzer shots rather than one projectile model. U.S. Army sources define a complete shot as fuze, primer, projectile, and propelling charge, while manufacturer and conflict records show high-explosive, extended-range, inert, precision-guided, smoke, illumination, cluster, white-phosphorus, and charge-system variants across NATO and NATO-compatible artillery use.

Sources

M777 Lightweight Towed HowitzerPublisher: BAE Systems | Note: Supports M777 manufacturer, background, mobility, operator, and 155 mm 39-caliber specification context. | Accessed: 2026-06-19U.S. Upgrades and Orders More Lightweight BAE Systems HowitzersPublisher: BAE Systems | Note: Supports lightweight build, titanium and aluminum construction, helicopter mobility, and the U.S.-UK production program total of 1,071 guns. | Accessed: 2026-06-26U.S. Army awards BAE Systems $162 million contract for new M777 structuresPublisher: BAE Systems | Note: Supports 2025 production-restart context for new M777 major structures and the Sheffield/U.S. supply-chain production plan. | Accessed: 2026-06-30BAE Systems awarded $146 million for M776 cannon productionPublisher: BAE Systems | Note: Supports 2026 U.S. second-source production context for the M776 cannon used as the M777's main armament. | Accessed: 2026-06-30M777 Ultralightweight Field HowitzerPublisher: Army Technology | Note: Supports additional system background and M777A1/M777A2 variant context. | Accessed: 2026-06-19Picatinny engineers seek to double range of modified howitzerPublisher: U.S. Army | Note: Supports M777ER demonstrator context, including modification from an M777A2 and the extended-range test goal. | Accessed: 2026-06-30Picatinny engineers double range with modified M777A2 Extended Range howitzerPublisher: U.S. Army | Note: Supports M777ER test details, including the 55-caliber tube, Watervliet Arsenal manufacture, Yuma firings, and demonstration-path caveats. | Accessed: 2026-07-06M777 HowitzerPublisher: Military.com | Note: Supports additional system background. | Accessed: 2026-06-19M777 155mm lightweight towed howitzerPublisher: Australian Army | Note: Supports Australian Army specifications, projectile classes, and CH-47/C-17A/C-130J transport context for the M777. | Accessed: 2026-07-06GICHD Explosive Ordnance Guide for UkrainePublisher: Geneva International Centre for Humanitarian Demining | Note: Supports M777 ammunition-compatibility context for M795 high-explosive projectiles and M549-family rocket-assisted projectiles in the Ukraine ordnance guide. | Accessed: 2026-07-07U.S. Marines with HMH-461 conduct M777 towed 155 mm howitzer transport during Exercise Northern Strike 24Publisher: DVIDS | Note: Supports CH-53K carriage of an M777 towed 155 mm howitzer during Exercise Northern Strike 24. | Accessed: 2026-06-282CR discusses Stryker modification for howitzer crewsPublisher: DVIDS | Note: Supports M1083 Medium Tactical Vehicle towing context for M777A2 howitzer crews and a Stryker prime-mover test concept. | Accessed: 2026-07-06M777 Light Towed Howitzer imagePublisher: Wikimedia Commons | Note: Supports image provenance for the primary M777 gallery image; Commons lists Jonathan Mallard as author and CC BY 2.0 licensing. | Accessed: 2026-06-223rd Cavalry Regiment M777 howitzer imagePublisher: Wikimedia Commons | Note: Supports image provenance for the 2014 Operation Inherent Resolve M777 gallery image; Commons identifies it as a U.S. Army public-domain work. | Accessed: 2026-06-22U.S. Army M777 howitzer imagePublisher: Wikimedia Commons | Note: Supports image provenance for the U.S. Army M777A2 gallery image; Commons identifies it as a U.S. Army public-domain work. | Accessed: 2026-06-22Fact Sheet on U.S. Security Assistance to UkrainePublisher: U.S. Department of Defense | Note: Supports broad Ukraine security-assistance context for U.S.-provided 155 mm howitzers and artillery rounds, without identifying the M777 by name. | Accessed: 2026-06-19Russians advance on war's front line in eastern UkrainePublisher: Associated Press | Note: Supports 2014 Russia-Ukraine War direct conflict use by documenting Ukrainian soldiers firing a U.S.-supplied M777 howitzer at Russian positions in Donetsk region in June 2022. | Accessed: 2026-06-20U.S. Marines conduct artillery strikes against ISIS in SyriaPublisher: U.S. Central Command | Note: Supports 2014 War Against the Islamic State direct conflict use under Operation Inherent Resolve: 2014 Operation Inherent Resolve: fired by U.S. Marines in northern Syria for coalition partner fire support against ISIS. | Accessed: 2026-06-20DVIDS Al Asad M777A2 firingPublisher: DVIDS | Note: 2014 War Against the Islamic State: documents 3rd Cavalry Regiment Field Artillery Squadron troops firing an M777A2 in Iraq while supporting Iraqi Security Forces under Operation Inherent Resolve. | Accessed: 2026-07-06Video: Things That Go Boom!Publisher: U.S. Department of Defense | Note: 2001 War in Afghanistan: used by U.S. soldiers at Camp Dahlke to provide artillery fire support for U.S. and Afghan forces. | Accessed: 2026-06-20US Marines fire Excalibur from record range in AfghanistanPublisher: Raytheon | Note: 2001 War in Afghanistan: documents U.S. Marines in Helmand province firing an Excalibur projectile from an M777 howitzer. | Accessed: 2026-06-30M777 Mods Army budget justificationPublisher: U.S. Army | Note: Supports FY2025 unit cost, fielding history, range, Excalibur compatibility, titanium construction, hydraulics, and digital fire-control modernization. | Accessed: 2026-06-26New howitzer makes thunderous debutPublisher: Headquarters Marine Corps | Note: Supports the M777's first Marine Corps fielding on 24 May 2005. | Accessed: 2026-06-26Howitzer booms at PendletonPublisher: Marine Corps Base Camp Pendleton | Note: Supports the first Camp Pendleton firing of the M777 on 11 August 2005. | Accessed: 2026-06-26Austin to Host Meeting in Germany to Discuss Ukraine's Long-Term Defense NeedsPublisher: U.S. Department of Defense | Note: Supports the 21 April 2022 announcement that 72 M777 howitzers would go to Ukraine in the latest security assistance package. | Accessed: 2026-06-26Canada announces artillery and other additional military aid for UkrainePublisher: Government of Canada | Note: 2014 Russia-Ukraine War: documents Canadian delivery of a number of M777 howitzers and associated ammunition to Ukraine's security forces. | Accessed: 2026-07-06Working together for UkrainePublisher: Australian Department of Defence | Note: 2014 Russia-Ukraine War: documents Australian-donated M777 howitzers bound for Ukraine and says Australia gifted six M777 howitzers with ammunition. | Accessed: 2026-07-06Marines test 3 big guns in week-long artillery experimentPublisher: Marine Corps Times | Note: 2003 Iraq War: image caption documents Marines firing an M777A2 high-explosive round at Camp Fallujah and identifies the battery as the first to employ the cannon in combat. | Accessed: 2026-06-30US Army awards Raytheon $31.8 million contract for continued Excalibur productionPublisher: Raytheon | Note: Supports Excalibur round cost context and the stated 464-round contract quantity. | Accessed: 2026-06-26