Rimfire cartridges are a small group in terms of number of types. On the other hand, the 22 Long Rifle cartridge is the cartridge produced in the largest quantity in the world.
Scholarly sources differ somewhat on the author of the first rimfire cartridge, mostly Louis Flobert is mentioned. The guns produced by this gunmaker, and later by many other manufacturers, became widespread and so did the cartridges for them. Flobert cartridges are still in production today. The shatter component of these cartridges was also the propellant, and only later was a small amount of powder added, although it is possible to read somewhere that powder was added from the beginning of production. A logical development followed, whereby in an attempt to increase the performance of the cartridge, the calibre, the length of the cartridge case and the powder charge were increased. However, the weak walls of the cartridge case, necessary for proper function, did not tolerate high pressures when fired, and this was the limit of the performance of rimfire cartridges. This is also why most of these cartridges did not survive the transition to the more powerful smokeless powder. There is another fact that put these bullets at a disadvantage compared to centerfire bullets. It's the practical impossibility of reloading. Many shooters, hunters, and trappers, especially in the US, used spent cartridges for reloading, which made shooting much cheaper. They are still reloaded today, and that is a topic for a separate article. However, one round with a rimfire was reloaded. It is the Austro-Hungarian military cartridge 14 mm Wänzel. As part of the training investigation, the used cartridge was straightened on a special anvil and the live cartridge was reassembled. However, such reloaded cartridges were used only for training on the firing range. There were also several cartridge calibers that were reconstructed from rimfire to centerfire. Examples include the English 442 Rev. cartridge or the aforementioned RU 14mm Wänzel rifle cartridge. Neither of these cartridges are in use anymore and have become collector's items. There are several calibers of Flobert cartridges in production today, 22 Short and 22 Long Rifle cartridges, 22 Winchester Magnum RF, 17 Hornady RF, and several other less common cartridges.
The principle of the rimfire is quite simple. The shatter is placed inside the cartridge case in an expanded rim all the way around. The firing pin deforms the cartridge, violently pushing together the two arms of the flared rim, between which the shatter compound is located, and thus ignition occurs. Attached is a drawing of the rimfire cartridge and several representatives of this group of cartridges.
One final note for the beginning collector. There are several types of so-called covered centerfire, where the bullet appears to be rimfire (the primer is not visible), for example Benet, Perrin, etc. In such a case, some knowledge is required to distinguish between these bullets. Photo of cartridges by.
Source. Hýkel, Ing. Malimánek "Bullets with marginal ignition" ed. Motoma s.r.o. 2003
Vlevo jsou náboje dosud vyráběné, 6mm Flobert, 22 Long Rifle, 22 Win. Mag. RF, vpravo jsou historické 44 Henry Flat a 41 Derringer