7 mm STW

The 7 mm STW (Shooting Times Westerner) began as a wildcat rifle cartridge developed by Layne Simpson in 1979. It is an 8 mm Remington Magnum case that has been "necked down" (narrowing the case opening) by 1 mm to accept 7 mm (.284 in) bullets. This cartridge is named after the magazine Shooting Times where Layne Simpson is a regular contributor.

Background
The 7mm STW graduated to commercial status when it was officially recognized by SAAMI in 1996. Remington Arms Company was one of the first large ammunition companies to produce this cartridge in 1997, with others like Federal Cartridge Company, A-Square, and Speer also carrying it. All mass-market US riflemakers now offer a selection of production models chambered for the 7mm STW, which has established a reputation as a fine long-range deer and medium game rifle.

Performance
The only the commercial 7mm cartridge to have more power than the 7mm STW is the 7mm Remington Ultra Magnum. Dimensionally and ballistically, there are similarities between the 7mm STW and the 6mm cartridge based on the .375 H&H Magnum case necked down, known as the .244 H&H Magnum.

Categories
Cartridge:rifles