http://www.inetres.com/gp/military/i...ifle/M107.html
According to that website, the M82/M107 can only use:
* MK211 Mod 0, Caliber .50 API Cartridge
* M33, Caliber .50 Ball Cartridge
* M17, Caliber .50 Tracer Cartridge
* M8, Caliber .50 API Cartridge
* M20, Caliber .50 APIT Cartridge
* M1A1, Caliber .50 Blank Cartridge
While also giving the penetration of the M903 SLAP round @ 34mm @ 500m, and 23mm @ 1,200m.
http://www.inetres.com/gp/military/i...g/50_ammo.html