.22 Spitfire
Overview
 
The .22 Spitfire is an American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

  rifle
Rifle
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves cut into the barrel walls. The raised areas of the rifling are called "lands," which make contact with the projectile , imparting spin around an axis corresponding to the...

 cartridge
Cartridge (firearms)
A cartridge, also called a round, packages the bullet, gunpowder and primer into a single metallic case precisely made to fit the firing chamber of a firearm. The primer is a small charge of impact-sensitive chemical that may be located at the center of the case head or at its rim . Electrically...

.

Designed by Melvin M. Johnson
Melvin Johnson
Melvin Maynard Johnson Jr. was an American designer of firearms, lawyer, and US Marine Corps officer.Born into an affluent Boston, Massachusetts family, he was commissioned into the Marine Corps Reserve in 1933 as a Second Lieutenant and completed Harvard Law school in 1934...

 of Johnson Guns Inc. for their conversion of the M1 carbine
M1 Carbine
The M1 carbine is a lightweight, easy to use semi-automatic carbine that became a standard firearm for the U.S. military during World War II, the Korean War and the Vietnam War, and was produced in several variants. It was widely used by U.S...

, this wildcat
Wildcat cartridge
A wildcat cartridge, or wildcat, is a custom cartridge for which ammunition and firearms are not mass produced. These cartridges are often created in order to optimize a certain performance characteristic of an existing commercial cartridge.Developing and using wildcat cartridges does not...

 was introduced in 1963. It was based on the .30 carbine
.30 Carbine
The .30 Carbine is the cartridge used in the M1 Carbine introduced in the 1940s. It is an intermediate round designed to be fired from the M1 carbine's 18-inch barrel.-History:...

, necked-down to .22 (5.7mm).

It is suitable for rabbit
Rabbit
Rabbits are small mammals in the family Leporidae of the order Lagomorpha, found in several parts of the world...

s, coyote
Coyote
The coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...

s, or other varmints, and has potential as a military round.
  • Barnes, Frank C., ed. by John T. Amber. "MMJ-5.7mm", in Cartridges of the World, pp. 127 & 143.
 
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