The Austrian Pfeifer-Zeliska. 600 Nitro Express Magnum. This is a custom, handmade pistol. It has a bullet weight of 900 grains, a muzzel velocity of 1950 fps. The muzzle energy produced is 7591 ft/lbs. It is 3 times more powerful then the Smith and Wesson's most powerful pistol, the. 50 Magnum.