7.62x51mm NATO is essentially a military version of '''.308 Winchester''', a civilian hunting cartridge of identical dimensions originally intended for the Winchester Model 70, a popular hunting rifle.
There are very slight differences in real life between the two cartridges (.308 Winchester develops roughly 4% more pressure than 7.62x51mm NATO), which are too small to be considered important; [https://en.wikipedia.org/wiki/Sporting_Arms_and_Ammunition_Manufacturers%27_Institute The SAAMI organization] considers it safe to interchange .308 Winchester and 7.62x51mm NATO. As far as the game is concerned, the cartridges are identical in all but name, and it is considered acceptable to use either designation to refer to the same cartridge.
7.62x51mm is typically pronounced ''seven point six two by fifty-one millimeters''. It is also acceptable to pronounce 7.62 ''seven six two''.<br/>