|Parent case||.22 Short|
|Bullet diameter||.222 in (5.6 mm)|
|Neck diameter||.226 in (5.7 mm)|
|Base diameter||.226 in (5.7 mm)|
|Rim diameter||.278 in (7.1 mm)|
|Rim thickness||.043 in (1.1 mm)|
|Case length||.613 in (15.6 mm)|
|Overall length||.888 in (22.6 mm)|
|Source(s): Cartridges of the World|
.22 Long is a variety of .22 caliber (5.6 mm) rimfire ammunition. The .22 Long is the second-oldest of the surviving rimfire cartridges, dating back to 1871, when it was loaded with a 29 grain (1.9 g) bullet and 5 grains (0.32 g) of black powder, 25% more than the .22 Short on which it was based. It was designed for use in revolvers, but was soon chambered in rifles as well, in which it gained a strong reputation as a small game cartridge, and sold very well.
In 1887 the .22 Long case was combined with the heavier 40 grain (2.6 g) bullet of the .22 Extra Long of 1880 to produce the .22 Long Rifle giving a longer overall length, a higher muzzle energy and superior performance as a hunting and target round, rendering the .22 Long and .22 Extra Long obsolete. Many firearms designed for the .22 Long Rifle will chamber and fire the shorter round, though the .22 Long generally does not generate sufficient energy to operate semi-automatic guns. The one prominent survivor of the .22 Long is the .22 CB Long, a long-cased version of the .22 CB.
While the original .22 Long loading used the same powder charge as the .22 Long Rifle, the .22 Long bullet was significantly lighter, and the combination did not result in higher velocities for the .22 Long when fired from a rifle. The large barrel volume to chamber volume ratio of a .22 rimfire rifle means that the powder gasses have expanded as far as they can well before the bullet reaches the muzzle of a normal length rifle barrel, and the light .22 Long bullet has less inertia than the .22 Long Rifle. This means that the .22 Long bullet actually slows down significantly before it exits the barrel. For farmers, or for those who only hunted small game such as squirrel or cottontail rabbit, the differences in performance between the .22 Long and .22 Long Rifle cartridges were of little importance. The quieter report and lower penetration of the .22 Long cartridge were often seen as desirable qualities.
Since the .22 Long Rifle performs as well in a short handgun barrel as the .22 Long and outperforms it significantly in a long rifle barrel, the development of the .22 Long Rifle assured the .22 Long's path to obsolescence.
Descendants of the .22 Long still live on. Modern Hypervelocity loadings of the .22 Long Rifle use bullets as light as 30 grains (1.9 g), and modern blends of powder to make full use of a rifle barrel to generate velocities far higher than normal loads, and chamber pressures high enough to cycle semi-automatic firearms reliably. The most well known of these is the CCI Stinger, which actually goes so far as to stretch the case length slightly, so that with the short, light bullet, the overall length is still within the max overall length for the .22 Long Rifle.
The .22 Long is still produced as it survived the change over to smokeless powders. CCI currently loads a high-velocity .22 Long with a MV of 1215 fps and a ME of 95 ft. lbs.
- Case: 0.613 in (15.6mm)
- Overall: 0.888 in (22.6mm)
- Bullet weight: 29 gr (1.88 g)
- Twist: 1 in 20 for dedicated firearms
- .22 Extra Long
- .22 Long Rifle
- .22 Short
- 5 mm caliber
- List of rifle cartridges
- List of rimfire cartridges
- Cartridges of the World 11th Edition, by Frank C. Barnes, Edited by Stan Skinner, Gun Digest Books, 2006, ISBN 0-89689-297-2, pp. 490, 492
- Hawks, Chuck. "A Brief History of .22 Rimfire Ammunition". chuckhawks.com. Retrieved 31 October 2013. CS1 maint: discouraged parameter (link)
- "22 Long Rifle Ammunition Specifications and Experience". flat5.net. Archived from the original on 2013-11-02. Retrieved 31 October 2013. CS1 maint: discouraged parameter (link)
- "Some interesting .22 Ammo information". smith-wessonforum.com. Retrieved 31 October 2013. CS1 maint: discouraged parameter (link)
- ".22 Long Rifle High Velocity And Hyper Velocity Ballistics". gundata.org. Retrieved 31 October 2013. CS1 maint: discouraged parameter (link)
- Rocketto, Hap. "[PDF]A Short History of the .22 Rimfire Cartridge" (PDF). csrra.com. Archived from the original (PDF) on 2013-11-02. Retrieved 31 October 2013. CS1 maint: discouraged parameter (link)