The .257 STW (Shooting Times Westerner) is a high-velocity rifle cartridge based on the .7mm Shooting Times Westerner (7mm STW) case, which itself is a necked-down version of the .8mm Remington Magnum. Introduced in the early 1990s, the .257 STW is designed for long-range shooting and medium-sized game hunting, such as deer or pronghorn.
This cartridge is known for its flat trajectory and high muzzle velocity, typically sending a .257 caliber bullet (6.5mm) downrange at speeds exceeding 3,500 feet per second (fps). The high velocity and flat trajectory make it suitable for long-range shots, reducing the need for significant holdover.
The .257 STW is less common than other hunting cartridges, and as such, handloading is often necessary for those who choose to use it. It is particularly favored by enthusiasts who prioritize long-range accuracy and performance over the availability of factory ammunition.
Given its powerful ballistics, it produces significant recoil and requires rifles with strong actions and barrels to handle the increased pressures.