Cap pistol

A cap gun, cap pistol, or cap rifle is a toy gun that creates a loud sound simulating a gunshot and a puff of smoke when a small percussion cap is exploded. Cap guns were originally made of cast iron, but after World War II were made of zinc alloy, and most newer models are made of plastic.

Cap guns get their name from the small discs of shock-sensitive explosive compounds (roughly 1.4 to 1.6 millimetres (0.055 to 0.063 in) in diameter) that provide the noise and smoke, effectively the same as the Maynard tape primer and percussion caps used in real firearms of the mid to late 1800s but usually smaller and made from cheap plastic or paper. Some are arranged in plastic rings of eight or twelve. There are also single caps, roll caps (of 50 to 500), disk caps, and cap strips all of which are actually extremely small versions of percussion fireworks. Armstrong's mixture is often used today as the explosive, but previously the tiny powder charge was a simple mixture of potassium perchlorate, sulfur, and antimony sulfide sandwiched between two paper layers which hold in the gases long enough to give a sound report when the cap is struck.

Cap guns first appeared following the end of the American Civil War in the mid-1860s, when firearms companies experimented with toy guns in order to stay in business.

Cap guns became especially popular when the heroes of cinema and television rode through the West ridding the territories of villains. Many cap guns were named after or endorsed by leading matinee idols like Roy Rogers, Gene Autry, Hopalong Cassidy, The Lone Ranger, Tonto, Dale Evans, Marshal Matt Dillon, or any of countless others.

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