Sierra GameChanger .300 Winchester Magnum 180 grain Sierra Tipped GameKing Brass Cased Centerfire Rifle Ammo, 20 Rounds, A4680–07

Introduced in 1963, the new 300 Winchester Magnum used the same case length as the rest of the Winchester Magnum family, although the shoulder was moved forward to allow greater powder capacity. This increased capacity made it one of the most potent commercial 30 caliber magnum capable of use in a standard (30-06 length) action. The 300 Winchester Magnum is primarily a hunting cartridge, but has enjoyed considerable success as a 1000 yd target round. As a big game cartridge, it is ample for any North American big game species. With its flat trajectory, it is well suited to the long-range shooting conditions frequently encountered in western big game hunting.