"A rimfire is a type of firearm
cartridge. It is called a rimfire because instead of the firing pin
striking the primer cap at the center of the base of the cartridge
to ignite it (as in a centerfire cartridge), the pin strikes the
base's rim. The rim of the rimfire cartridge is essentially an
extended and widened percussion cap which contains the priming
compound, while the cartridge case itself contains the propellant
powder and the projectile (bullet). Once the rim of cartridge has
been struck and the bullet discharged, the cartridge cannot be
reloaded, because the head has been deformed by the firing pin
impact. While many different cartridge priming methods have been
tried, only rimfire and centerfire survive today in significant use.
Rimfire cartridges are limited to low pressure calibers due to the thin case they require for the firing pin to be able to crush the rim and ignite the primer. Although rimfire calibers up to .44 (11 mm) were once common, modern rimfires tend to be of caliber .22 (5.5 mm) or smaller. The low pressures mean that rimfire firearms can be very light and inexpensive, which has helped lead to the continuing popularity of small caliber rimfire cartridges." From: Rimfire ammunition. (2009. February 28). In Wikipedia, The Free Encyclopedia. Retrieved 18:29. March 11, 2009. from en.wikipedia.org
When it comes to rimfire ammo we always start with 22 caliber and then move on to: 17 HMR, 17 mark 11, 17 mk 11, 22 Ammo, 22 ammunition, 22 blanks, 22 cal, 22 Hollow points, 22 long rifle, 22 mag, 22 magnum, 22 shotsells, 22 shorts, BB Caps, Bellot, CB Caps, CCI, Dahlonega, Eley, hyper Velocity, Lapua, LaserMatch, pistol match, PMC, Remington, rifle match, rimfire ammunition, RWS, Sellier, Subsonic, Winchester.
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