 Beside the 6.5×63mm Messner Magnum rimless rifle cartridge, Messner also designed a rimmed version for break action rifles of the cartridge called the 6.5×63mmR Messner Magnum.Due to the large case capacity in relation to the 6.5 mm (.264 inch) calibre bore size the 6.5×63mm Messner Magnum is very harsh on barrels.It typically wears out a rifle barrel in 500 to 1000 rounds.