There is a plethora of .22 centrifuge cartridges firing bullets of about the same size as the .22R/F but at much higher velocity. Those usually encountered in Britain are, in ascending order of power, the .22 Hornet, the .222 Remington , the .223 Remington (which is the same as the 5.56mm NATO cartridge) and the 22/250 Remington. Very occasionally you may come across a .220 Swift. You may also meet or be asked about the .17 Remington which fulfills the same function using a lighter bullet of around 20 grains weight at about 4000 feet per second muzzle velocity.Don’t be fooled by the names; all but the .17 Remington fire bullets of .224 inch diameter. Bullet weight in the .22 calibers may range from 40 to about 70 grains. (There are 437.5 grains to the ounce and 7000 grains to the pound).

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