The M777 howitzer is a British towed 155 mm artillery piece in the howitzer class. It is used by the ground forces of Australia, Canada, Colombia, India, Saudi Arabia, Ukraine, and the United States. It was first used in combat during the War in Afghanistan.
The M777 is manufactured by BAE Systems' Global Combat Systems division. Prime contract management is based in Barrow-in-Furness in the United Kingdom as well as manufacture and assembly of the titanium structures and associated recoil components. Final integration and testing of the weapon is undertaken at BAE's facility in Hattiesburg, Mississippi. Depending on the year, contract and systems package, the M777 has been exported for individual unit costs including US$2.025 million (in 2008) and $3.738 million (in 2017).
Design
The M777 began in 1987 as the Ultralight Field Howitzer (UFH), developed by Vickers Shipbuilding and Engineering's (VSEL) Armaments Division in Barrow-in-Furness, UK. VSEL was bought by BAE Systems after the UFH prototypes had been manufactured and demonstrated, and consequently BAE became responsible for future design refinements and renamed the gun "M777". Upon taking over responsibility for the weapon, BAE "Americanized" to a large degree the construction and assembly through its US-based BAE Systems Land and Armaments group. The M777 now uses about 70% US-built parts including the gun barrel (designated M776), which is manufactured at the Watervliet Arsenal.
With a weight of , the M777 is 41% lighter than the M198 howitzer it replaces. Much of the weight reduction is due to the extensive use of titanium. The gun barrel serves as the towing bar, with the connecting ring forged as a projection of the muzzle brake. The M777 can be transported by helicopter sling-load, transport aircraft such as the Lockheed C-130 Hercules, or towed by air-braked vehicles weighing over , such as the FMTV and MTVR medium tactical vehicles. The minimum gun crew required is five, compared to a previous nine. The normal crew is eight. With a minimal emergency crew, the rate of fire is decreased.
The M777A1 and M777A2 use a digital fire-control system similar to that found on self-propelled howitzers such as the M109A6 Paladin to provide navigation, pointing and self-location, allowing it to be put into action quickly.
The Canadian M777 in conjunction with the traditional "glass and iron sights/mounts" uses a digital fire control system called the Digital Gun Management System (DGMS) produced by Leonardo MW with components of the Indirect Fire Control Software Suite (IFCSS) built by the Firepower team in the Canadian Army Land Software Engineering Centre. The Leonardo MW portion of the system, known as LINAPS, had been proven previously through earlier use on the British Army 105 mm L118 Light Gun.
The M777A2 may be combined with the M982 Excalibur 155mm GPS-guided munition, which allows accurate fire at a range of up to . This almost doubles the area covered by a single battery to about . Testing at the Yuma Proving Ground by the US Army placed 13 of 14 Excalibur rounds, fired from up to , within of their target, suggesting a circular error probable of .
In June 2012, Golf Battery, 2nd Battalion, 11th Marines, out of Camp Pendleton, California, fired the M982 Excalibur against insurgents at a range of in Helmand Province, Afghanistan. This was the longest operational shot in the history of the M777 howitzer, and the longest operational barrel artillery shot in history for the Marine Corps.
Usually a barrel on a modern artillery system, like the M777, must be replaced after firing up to 2,500 rounds.
Variants
M777 – Gun with optical fire control
M777A1 – Digitization upgrades, with the addition of an onboard power source, satellite global positioning, inertial navigation, radio, Gun Display Unit (GDU) and Section Chief Assembly (SCA). M777A2 – Block 1A software upgrade. Addition of an Enhanced Portable Inductive Artillery Fuze Setter (EPIAFS) to enable Excalibur and precision munition compatibility. M777ER – Upgrade created by the Extended Range Cannon Artillery (ERCA) project to extend range from . Modified with a longer 55-caliber, barrel and supercharged propellant firing the XM1113 rocket-assisted projectile. M777C1 – M777 with DGMS (Canada)