|.22 Extra Long|
|Place of origin||United States|
|Bullet diameter||.223 in (5.7 mm)|
|Neck diameter||.225 in (5.7 mm)|
|Base diameter||.225 in (5.7 mm)|
|Rim diameter||.275 in (7.0 mm)|
|Rim thickness||.043 in (1.1 mm)|
|Case length||.750 in (19.1 mm)|
|Overall length||1.16 in (29 mm)|
|Source(s): Barnes & Amber 1972|
Introduced around 1880, the .22 Extra Long was used in Remington, Ballard, Wesson, Stevens, and later (1916) models of Winchester's M1902 and M1904 single-shot bolt-action rifles, as well as in Smith & Wesson revolvers.
Using the same 40 gr (2.6 g) outside-lubricated bullet later adapted for the much more common .22 Long Rifle, the Extra Long was loaded with 6 gr (389 mg) of black powder. Originally, it slightly outperformed the .22 LR, but was "not noted for great accuracy", while later smokeless loads achieved about the same muzzle velocity as the .22 LR.
As with the .22 Winchester Automatic and .22 Remington Automatic, the .22 Extra Long will not chamber correctly in .22 Long Rifle weapons. Because it is very dimensionally-similar, however, the shorter .22 Short, .22 Long, and .22 LR will chamber in weapons designed for it (in the same way .38 Special ammunition can be fired in .357 Magnum weapons, or .44 Special rounds in .44 Magnums).
The .22 Extra Long ceased to be offered commercially in 1935.