The largest of the Weatherby cartridges, this round was commercialized in 1958. Bertram brass does not have the double radius shoulder but once the brass is fired this will be formed. Since the cartridge headspaces on the belt, the shoulder position is not important and once fired will be a perfect fit for your rifle. It does not need to be fireformed to be used. This brass is packaged in lots of 20. Shipping weight is 435 g/20 cases.