The XM307 Advanced Crew Served Weapon (ACSW) is a developmental 25 mm belt-fed Grenade Machine Gun with smart shell capability. It is the result of the OCSW or Objective Crew Served Weapon project. It is lightweight and designed to be two-man portable, as well as vehicle mounted. The XM307 can kill or suppress enemy soldiers out to 2,000 metres (2,187 yd), and destroy lightly armored vehicles, watercraft, and helicopters at 1,000 metres (1,094 yd). But the project was canceled in 2007.
The system is under development by General Dynamics Armament and Technical Products for the U.S. Army Tank-Automotive and Armaments Command (TACOM). As a part of the Small Arms Master Plan (SAMP) program, it is intended to either replace or supplement the Mk19 automatic grenade launcher and the M2 heavy machine gun. It fires 25 mm point-detonating and air burst style ammunition, including HE, and HEAT at a cyclic rate of 260 rounds per minute and has an effective range up to 2 kilometers.
The primary advantage of the XM307 is its attenuated recoil system. The weapon controls recoil to a degree that a large tripod and heavy sandbags are not required to effectively employ this weapon. Because of this reduced recoil impulse and light weight, other mounting options are also possible such as small unmanned vehicles and aircraft. Its airburst rounds also make it much easier to hit enemies behind walls that could cause collateral damage if thoroughly shot through. They do not have to shoot through the wall, just through a window or over the top and kill the people behind the cover, leaving the structure of the building intact. Also, in under 2 minutes, it can be converted into the XM312, a .50 cal version for infantry and light anti-armor support.
- System weight: 50 lbs (22 kg) (Gun, mount, and fire control).
- Fire Control: Full solution, day/night.
- Portability: Two-man portable & vehicle mountable.
- Rate of Fire: 250 rounds per minute, automatic.
- Dispersion: Less than 1.5 mils, one sigma radius.
- Range: Lethal and suppressive to 2,000 meters.
- Ammunition: High-explosive air bursting, armor piercing, and training (HE, AP, TP, TP-S).
A Remotely Operated Variant (ROV) for the Future Combat Systems family of vehicles is also under development. The weapon system, which would be mounted on the vehicle, will be remotely operated from within the vehicle.
- May 2004 - The development phase is funded through FY 2007.
- December 2005 - Funding granted for ROV variant.
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- XM312 - (.50 BMG version of the XM307)
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