The .480 Ruger By Chuck Hawks Hornady did the development work on the .480 Ruger cartridge and Ruger came up with a revolver to fire it. Ruger changed the name from .475 Ruger to .480 Ruger to give the cartridge a unique identity, but the actual bullet diameter is .475 inch., and .480 Ruger cartridges can be chambered and fired in .475 Linebaugh revolvers. The SAAMI maximum average pressure for the .480 Ruger is pegged at 48,000 psi, slightly below the 50,000 psi allowed for the .454 Casull. The ballistics of the current .480 factory loads call for a 325 grain bullet at a muzzle velocity of 1350 fps from a 7.5" revolver barrel. Muzzle energy is 1315 ft. lbs. At 100 yards the bullet is still rolling along at about 1075 fps and carrying 835 ft. lbs. of energy. That is, as intended, about midway between the .44 Magnum and the .454 Casull in power. From a pistol zeroed at 100 yards the trajectory of the factory loads should have a midrange rise of about 3 inches, which makes 100 yards the logical distance at which to zero a .480 revolver for big game hunting. Suitable powders for the .480 include H110, Lil'Gun, and W296. Do not reduce loads below the recommended minimum with these powders. Hornady makes two bullets for the .480 Ruger and .475 Linebaugh, a 325 grain XTP-MAG and a 400 grain XTP-MAG. Here are some .480 specifications of interest to reloaders: bullet diameter .475", maximum COL 1.650", maximum case length 1.285", trim to 1.275". Reloading data is available online from the Hodgdon Powder Company, Speer, Hornady, and others. According to the sixth edition of the Hornady Handbood of Cartridge Reloading a minimum load of 19.8 grains of H110 powder behind their 325 grain bullet gave a MV of 1100 fps. A maximum charge of 27.3 grains of H110 gave a MV of 1500 fps. The same source shows that 17.4 grains of H110 can drive the Hornady 400 grain bullet to a MV of 1000 fps. A maximum load of 21.0 grains of H110 achieved a MV of 1200 fps with that bullet. These loads used Hornady cases and Winchester WLP primers, and were tested in a Super Redhawk revolver with a 9.5" barrel. Note: A full length article about the .480 Ruger can be found on the Handgun Cartridge Page. |
Copyright 2005, 2013 by Chuck Hawks. All rights reserved.
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