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

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Black powder had been in general use in muzzle loading firearms for many years so it was the propellant utilized in early metallic cartridges. Black powder consists of a mixture of potassium nitrate (saltpeter), charcoal (carbon), and sulfur in the approximate percentages 75, 15, and 10, respectively. Burning rate of the propellant, which is designated by an “F” system, is controlled by the particle size. A granulation known as FFFFg (very fine, often referred to as “4F”) is a very fast-burning form while a coarse granulation designated as Fg is comparatively slow burning. Black powder used most often in rifles is FFg (medium) while FFFg (fine) is used in handguns or rifles of small caliber.

The 41 Swiss (left) and 22 Short (right) illustrate the range of cartridges that were eventually produced in rimfire calibers.

One of the early designs for a self-contained cartridge is known as the pinfire, and it dates from about 1830 when Monsieur Casimir Le Facheux invented it in Paris. The cartridge contained a bullet, propellant (black powder), and a primer. However, the blow of the hammer was transmitted to the primer by means of a pin that stuck out of the side of the case at the rear. This meant that the cartridge had to be oriented in the chamber in such a way that the hammer would strike the pin to push it into the case to crush the primer. Although placing the cartridges in the firearm in the correct orientation made loading slow by today’s standards, it was still rapid compared to loading a muzzle-loader. With pinfire cartridges, there was also the possibility that the protruding pin could be struck accidentally which could force it into the case causing the cartridge to fire. From the standpoint of safety, the pinfire left a lot to be desired. However, cartridges of this type were fairly popular in Europe and some shotguns employed this type of cartridge.