Читать книгу The Gun Digest Book of .22 Rimfire. Rifles·Pistols·Ammunition онлайн

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The four approaches to firing metallic cartridges are illustrated here. The cartridges illustrate (left to right) teatfire, pinfire, rimfire, and centerfire types.

Teat fire cartridges were developed in the 1800s before rim fire cartridges were introduced.

A cartridge consists of a primer, propellant, projectile, and a case for these components. In order to ignite a propellant, some substance that explodes is needed. The cause of the explosion is actually percussion (crushing) that is the result of a spring-loaded striker (hammer or firing pin) changing positions at the time of firing. In order to have shot-to-shot uniformity (which results in accuracy), it is necessary to have the same amount of explosive (primer) ignited in the same way for each shot and have the same amount of propellant in each cartridge.

Early developments in muzzle-loading firearms included the flintlock and the caplock, which used a percussion cap. In the flintlock, the primer consisted of a small amount of fast-burning black powder of fine granulation (FFFFg) that was ignited by the sparks produced when a piece of flint struck a piece of steel known as the frizzen. The priming charge was held in the flash pan, which had a hole that led downward into the barrel where the main propellant charge was held. The gas resulting from the burning powder in the main charge provided the driving force to move the bullet down the bore.