Pfeifer Zeliska .600 Nitro Express revolver

The .600 Nitro Express Zeliska revolver is an Austrian single-action revolver produced by Pfeifer Waffen. Except for the Giant 1859 28mm Remington revolver, the Zeliska may be the largest handgun in the world, weighing in at 6 kilograms (13.23 lb) and having a length of 55 centimetres (21.65 in). The cylinder alone weighs 2 kilograms (4.41 lb). The Zeliska is one of the most powerful handguns in the world, producing a muzzle energy of 4,592 foot pounds (by comparison, a 14" revolver chambered in the .500 Bushwhacker cartridge achieves approximately 10% greater power, firing a 310 grain bullet at 2,714 ft/s for 5,071 ft. lbs. of muzzle energy^[1] or a 400 grain bullet at 2,403 ft/s for 5,130 ft. lbs. of muzzle energy^[2]). The weight of the handgun helps control the recoil, making controlled shooting possible. The capacity of a Zeliska is five .600 Nitro Express or .458 Win Mag rounds. The Zeliska fires a 900 grain (58.32 g) .600 Nitro Express slug at 1,516 ft/s (462 m/s, 1,663.2 km/h), compared to the 1,850-2,050 ft/s regulation level velocities typical of 28” barrel rifles chambered in the cartridge.^[3] The cost of a Zeliska revolver is $17,316. Each .600 Nitro Express round costs $40, making this gun very expensive to fire.^[4][5]

Loading is accomplished through a loading gate located on the right of the cylinder, similar to the Colt Single Action Army, upon which the Zeliska largely is based.^{[citation needed]}

Added features to the gun include gold-plated hammer, cylinder pivot, action and the gold-filled inscription on the gun indicating the company's address.^{[citation needed]}