The .44 Special (.44 S&W Special, 10.9×29mmR) is a revolver cartridge designed by Smith & Wesson and brought into production in 1907. Its parent case is the .44 Russian cartridge, also designed by Smith & Wesson.
The .44 Special was produced by S&W in 1907, coinciding with the release of their brand new revolver, which they called the New Century.
Efforts to convert the .44 Russian to smokeless powder were unsuccessful, with unsatisfactory ballistic performance. As a result, S&W lengthened the .44 Russian cartridge case by 0.2 inches, which increased the powder capacity. S&W designated this new cartridge as the .44 Special.
Typical loads in .44 Special actually duplicate the ballistic performance of the .44 Russian; this includes the .44 Russian's reputation for accuracy.
The .44 Special is a rimmed centerfire cartridge. It uses a large pistol primer, usually Boxer primed, and fires with a maximum pressure of 15,500 psi. It fires optimally in revolvers with a 1:20 rifling twist. Most bullets for this caliber weigh either 200 grains or 246 grains (the latter which closely matches the ballistics of the .44 Russian); other weights are offered, however.