Auction Changes

We've made important changes to how our auction works. Please take a moment to read the updates before you place your next bid.

See Auction Updates Details

300 WIN Mag Centerfire Ammunition

The .300 Winchester Magnum (also known as .300 Win Mag or 300WM) (7.62×67mmB) is a belted, bottlenecked magnum rifle cartridge that was introduced by Winchester Repeating Arms Company in 1963. The .300 Winchester Magnum is a magnum cartridge designed to fit in a standard rifle action. It is based on the .375 H&H Magnum, which has been blown out, shortened, and necked down to accept a .30 caliber (7.62 mm) bullet.