| .25-21 Stevens | |
| Origin: | United States |
| Type: | centerfire rifle |
| Design Date: | 1897[1] |
| Case Type: | rimmed straight-case |
| Bullet: | .257 |
| Neck: | .280 |
| Base: | .300 |
| Rim Dia: | .376 |
| Case Length: | 2.05 |
| Length: | 2.30 |
| Primer: | boxer, small rifle |
| Bw1: | 86 |
| Btype1: | (smokeless, factory load) |
| Vel1: | 1470 |
| En1: | 415 |
| Bw2: | 86 |
| Btype2: | (9gr smokeless) |
| Vel2: | 1610 |
| En2: | 498 |
| Bw3: | 86 |
| Btype3: | (5gr smokeless) |
| Vel3: | 1500 |
| En3: | 434 |
| Balsrc: | Barnes & Amber 1972 |
The .25-21 Stevens was an American centerfire rifle cartridge.
Designed by Capt. W. L. Carpenter, 9th U.S. Infantry, in 1897, the .25-21 was based on the longer .25-25. It was Stevens' second straight-cased cartridge (after the .25-25)[2] and would be used in the single shot Model 44 rifle, as well as the Model, which first went on sale in 1903. In addition, it was available in the Remington-Hepburn target rifle.
While the .25-25 was popular, the .25-21 offered "practically the same performance and was a little cleaner shooting." It was also found the usual 20or black powder charge of the shorter, bottlenecked .25-21 offered "practically the same ballistics" as 24or in the .25-25. It was highly accurate, reputedly capable of generating 0.51NaN1 groups at 100yd.
In power, the .25-21 was outpaced by the .25-20 Winchester[3] and .32-20 Winchester,[4] while today, even modern pistol rounds such as the .38 Super offer superior performance.[5]