Peterson Cartridge .338 Wby RPM Brass Rifle Brass Casing 50 Count. From small batch production lines to quality control department to your bench and on to the range. Match-grade is the standard that we strive to achieve so that our customers can maintain that standard all the way to the target. Specifications for Peterson Cartridge .338 Wby RPM Brass Rifle Brass Casing: Manufacturer: Peterson Cartridge Gun Type: Rifle Caliber: .338 Weatherby Rebated Precision Magnum Fabric/Material: Brass Package Contents: Peterson Cartridge .338 Wby RPM Brass Rifle Casing Peterson Cartridge 40067-R: .338 Wby RPM Brass Rifle Brass Casing 50 Count