The .22 Winchester Magnum, more commonly calle .22 WMR (for Winchester Magnum Rimfire) or .22 Magnum or simply .22 Mag, is a rimfire rifle cartridge. Commonly loaded with a 40 grain (2.6 g) bullet, it can deliver velocities in the 2,000 ft/s (610 m/s) range from a rifle barrel. It is also available with 30-grain (1.9 g) loads (2 g) and can achieve speeds of 2,300 ft/s (700 m/s).