Based on the .308 Win. cartridge of the post-World War II era, a 6 mm cartridge emerged shortly thereafter and has become one of America's favorite hunting rounds. The .243 Win. provides today's hunter and long-range shooter with versatility that is tough to beat.
Based off the earlier magnum cartridges like the .375 H&H Mag., Winchester developed a shortened magnum load for short-action rifles and introduced it in 2001 as the .270 Winchester Short Magnum (WSM).