Like all WSM calibres, the 7mm Winchester Short Magnum, or 7mm WSM, is a centrefire cartridge jointly developed by Winchester and the Browning Arms Company; it came onto the market in 2001. The 7mm WSM has a non-belted Magnum case similar to the 300 WSM and 270 WSM, necked to fit .284 (7.21 mm) bullets. However, the dimensions of the case at the shoulder base together with the shorter neck of the 7mm WSM prevent accidental chambering in 270 WSM and 300 WSM calibre guns. The external and terminal ballistics of the 7mm WSM compare closely with the 7 mm Remington Magnum, both of which use the same bullets. The 7mm WSM calibre is perfectly suited to use in mountains against all large European mammals such as mouflon, stag and boar, and against large American mammals such as elk. The ballistic performance of the 7mm WSM is excellent with 9.70-gram bullets, which is why Winchester offers a load with the remarkable and highly versatile Power Max Bonded, for any type of hunt. Flat trajectory, massive knock-down power and contained recoil perfectly define this excellent calibre.