The Barrett XM109 Anti-Materiel Payload Weapon, formerly known as the XM109 Objective Sniper Weapon, is a prototype semi-automatic anti-materiel rifle developed by the Barrett Firearms Manufacturing. It is chambered in 25×59 mm explosive ammo. It has a effective range of 2,000 meters but with much greater lethality, capable of destroying lightly armored vehicles with ease. Due to the high recoil from such a large round, Barrett is researching a recoil reduction system for the XM109. It's barrel is 17.5 inches, shorter in comparison to the M107's 20 or 29 inch barrel. It has a 5 round magazine.
Prototypes of the weapon were created in 2002, with at least 10 prototypes known to exist as of 2004. The XM109 and the XM500 anti-materiel rifle were both merged into the Anti-Materiel Rifle Congressional Program in 2006. The status of the weapon is not entirely clear; there have been no claims of it being either adopted or canceled.
The weapon uses a short-recoil system similar to the Barrett M82 which it is based on. The top receiver of the XM109 can be put on the lower receiver of the M82's receiver to form a fully-functional XM109 rifle.
The weapon uses 25×59mm grenades, similar to the XM25. The weapon's grenades are shaped like bullets, so they are able to bounce; albeit rarely. As the grenades the weapon uses are now available in airburst configurations, the weapon can technically fire around corners and tight spaces while still retaining lethality.