XM307 Ma-Deuce Replacement Gets More Investment
General Dynamics Armament and Technical Products Inc. of Burlington, VT received a $6 million modification to a cost-plus-award-fee contract for a remotely operated variant of the XM307 Advanced Crew Served Weapon System. Remote operation systems like the Rafael OWS, Thales SWARM, and the Recon/Optical CROWS allow a weapon to be sighted, rotated, and fired from inside a vehicle, trading off reduced situational awareness for less crew exposure to hostile fire.
The lightweight XM307 is being developed by General Dynamics under a 2004 contract worth up to $95 million through December 2007. It will replace the M2 .50 cal “Ma Deuce” machine gun, which has been in service since the 1920s. Here in the 21st century, the USA has had to ramp up .50 cal ammunition production because “Ma Deuce” remains one of the most requested weapons in the Iraqi theater of war. Truly a hard act to follow – but the future M307/ M312 has a few new tricks up its gun sleeve.
The 50-pound XM307 is actually intended to replace two “old reliables” on the battlefield. One is the 84-pound M2 .50 caliber heavy machine gun, which weighs in at 128 pounds with its tripod. The other is the two decades-old MK19 Mod-3 40mm grenade machine gun, a popular choice for some vehicles that offers devastating suppressive fire capabilities. It weighs 79 pounds, or 137.5 pounds with its tripod. Some US Special Forces currently use a different, lighter (63 pounds, 107 pounds with tripod) 53 H&K 40mm GMG as a man-portable “ace in the hole” when serious firepower is called for, but the XM307 would offer a common replacement for all.
Because of its light weight, there is even talk of having the XM307 replace some medium machine guns (7.62mm M240Bs). This might be an especially good option in naval roles, and on some wheeled vehicles and helicopters.
With its 25mm air-bursting, armor-piercing, and incendiary munitions, the XM307 offers a lighter alternative that still packs a lethal punch. Its 25mm ammunition consists of grenade-like rounds that are programmed to detonate at a given distance. Enemy in a trench? It detonates over their heads. Enemy in a building? Don’t spray the structure with conventional machine gun fire. Use the single-shot option, and put a couple shots through the window that detonate in the room and spray it with shrapnel. Even at $20 per 25mm bullet, the results will sometimes prove cost-effective as well as battlefield effective.
The revolutionary technology behind the air-burst munition involves integration of the fuse and fuse setter into the weapon’s fire control system. In a process that includes three microbursts of information, the fire control system lazes the target and determines the range. That information is transferred to the round through galvanic hard points as it is loaded into the chamber. The fuse reads the data, verifies it and retransmits it as a safety check. Multiple layers of coding and verification ensure accurate range data and protects against premature detonation of the round in or near the weapon.
General Dynamics is developing the new family of 25mm ammunition, while Raytheon is responsible for the full solution fire control. The fire-control system will include a laser range finder and a day-night sight, and can be upgraded to include other modern equipment as well. Kaman Daytron, Inc. produces the high explosive airburst fuse.
The major uncertainty with the XM307 is that this new computer controlled ammunition has not been used in combat yet. Until it is, no one will be quite sure just how much of an improvement it really is.
As a combination of insurance policy and flexibility option, therefore the .50-caliber XM312 is derived from the XM307, and can be created by replacing only five parts. What’s left is an upgraded version of the old M2 that weighs only one-third as much and is capable of firing all of the current .50-caliber ammunition. This includes, but is not limited to, the standard M33 ball round, the M8 armor-piercing incendiary (API), the M903 saboted light armor penetrator (SLAP), and the Mk 211 multipurpose round (penetrates, fragmentation and incendiary).
The one improvement the XM312 would not include is a rate of fire rapid enough to suit it for an anti-aircraft or anti-helicopter role. The existing M2 has shared this issue since before World War 2, however, and US troops seem to love it all the same.
The service plans to have the M307 and M312 in the hands of soldiers by FY 2008.
Work on the contract to beef up the M307’s remote operation capabilities will be performed in Burlington, VT and is expected to be complete by June 30, 2006. This was a sole source contract initiated on Sept. 19, 2005 by the Army Tank-Automotive and Armaments Command at Picatinny, NJ (W15QKN-04-C-1093).
Additional Readings & Sources
- DID – Ma Deuce Still Going Strong. The Army is also working on an “XM806″ lightweight .50 cal, which tops out at 45 pounds and reduces recoil by more than 60%. It seems set to claim the XM312’s intended lightweight HMG slot after 2012, while the hand-held XM25 personal weapon offers a slower but similar substitute for the XM307.
- GlobalSecurity.org – M307 Airbursting Weapon System Advanced Crew Served Weapon
- Defense Update – XM307 Advanced Crew-Served Weapon (ACSW)
- Strategy Page – US Army’s New Heavy Machine Gun
- GlobalSecurity.org – XM312 .50-Caliber (12.7mm) Machine Gun
- World Guns – General Dynamics 12.7mm / .50 XM312 Machinegun (USA)
- GlobalSecurity.org – M2 .50 Caliber [12.7mm] Machine Gun “Ma Duce” (DID: We think they mean “Ma Deuce” – “Ma Duce” would be Mussolini’s mother…)
- Special Operations Technology (Nov 19/06) – Firepower. Covers M2 improvements, GMG variants, and the new XM307.
- DID (Sept 1/05) – US Ammo Shortage: GD Now A Second Source Prime as it Delivers Guns, Ammo
- DID (Sep 28) – $29.4M in Contracts Related to 40mm Grenade systems
- Heckler & Koch – H&K Grenade Machine Gun, used by some US Special Forces. See also this tester’s report.
- Special Operations Technology (Feb 9/04) – Pulling the Trigger. Covers the Mk47 Striker system and other 40mm innovations on the way, including the technology behind computer-controlled air-bursting rounds.
- DID (Sept 16/05) – USMC Gladiators to Pack a SWARM
- DID re: CROWS (Aug 5/05) – $68M Provides Remotely-Operated Machineguns for Vehicles
- RAFAEL Overhead Weapons Station
- National Defense Magazine (July 2005) – Army Rewrites Small Arms Plans. Offers a good overview of developments in a number of areas. Note that DID has since covered the XM-8 system, and that the program status has changed.
- Army Magazine (Oct 2004) – Next-Generation Soldier Weapons