High Quality Content by WIKIPEDIA articles! The .327 Federal Magnum is a cartridge introduced by Sturm, Ruger and Federal Cartridge, intended to provide the power of a .357 Magnum in six shot, compact revolvers, whose cylinders only hold 5 rounds of the larger .357 Magnum cartridge. The .327 Federal Magnum is actually a super magnum having replaced the .32 H&R Magnum as the pinnacle of the cartridge diameter.