Do anyone know the history of the .500 HWP Magnum? Case length is 35,5 mm (1.4 inches) and it is very much like the .500 Linebaugh. In The Blue Book on Gun Values (24th Ed., pg. 713) it says that a HWP Industries made a stainless steel 5-shot “The Sledgehammer” revolver in cal. .500 HWP Magnum in 1989. Is this the same cartridge as the .500 Linebaugh?