Peterson Cartridge makes finished casings in the popular belted magnum calibers, like .300 Win Mag. and 7mm Rem Mag. According to president Derek Peterson, “We’re now offering belted magnum basic brass for those customers who want to form it into their favorite belted caliber.”

The origins of one of the most popular cartridges designed by Roy Weatherby date to the 1940’s, when he used the existing concept of a venturi shoulder for his famous double radius shoulder magnum cartridge known as the .300 Weatherby Magnum. The .300 Weatherby Magnum has been a favorite of long-range big game hunters since its formal introduction in 1944, largely due to its velocity and muzzle energy advantages over its contemporaries.

Peterson Cartridge Co. of Pittsburgh, PA today announced the addition of 6.5-300 Weatherby to its growing family of rifle casing calibers.