This information is derived from a combination of sources: manufacturer's specifications,
measuruments performed by the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI)
and approximation formulas devloped by Genitron.com.
Rankings shown here are based on a 5-inch pistol barrel. Rankings for guns of this caliber in our database will vary based on their actual barrel types and lengths.
In shooting competition the Power Factor is used to determine the competitive division in which a particular handgun/cartridge
can be used. It is a simple calculation of the bullet's mass times its muzzle velocity.
PF = bull. mass x muzzel vel.
TKO-Taylor Knock Out Formula
Developed by big-game hunter John Howard Taylor in the 1940's, this formula calculates the relative effectiveness of bullets for hunting game.
TKO = (bull. mass x muzzle vel. x bull. dia.)/7000
This cartridge was introduced by Winchester in 1979 to be used in the gas-operated Wildey pistol. Winchester's new pistol was not much of a success, but the powerful .45 Winchester Magnum cartridge was. The cartridge is essentially an elongated version of the .45 ACP round. It was the most powerful semi-auto cartridge of its time, until the introduction of the .50 Action Express in 1988.