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. The furthest hit from an Excalibur ammunition by the United States Army was in Iraq. 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) Ammunition M982 Excalibur M1128 projectile XM1113 M549A1 Service history Australia In 2008, the Australian Defence Force made a US Foreign Military Sales request for 57 M777A2s worth an estimated US$248m. Subsequently, 35 guns were purchased for the Australian Army. to re-equip the 1st Regiment, Royal Australian Artillery, the 4th Regiment, Royal Australian Artillery, and the 8th/12th Regiment, Royal Australian Artillery, to replace 155 mm M198s and 105 mm L119 Light Guns. The first deliveries of M777A2 began in late 2010. An additional 19 guns will be bought directly from American production lines to enable a total of six batteries. Concurrently, the Australian Army has