 The 8mm Remington Magnum case has functioned as the parent case for the 7mm STW, which is essentially a 7 mm (.284 caliber) necked-down version of the 8mm Remington Magnum.Designed by Layne Simpson, Editor of "Shooting Times" magazine, the wildcat status of the 7mm STW ended in 1996 when it got SAAMI certified and became an officially registered and sanctioned member of the 8mm Remington Magnum "family" of magnum rifle cartridges.With top handloads pushing a 150 grain bullet at nearly 3,400 feet per second, it is one of the fastest mid-bore rifle cartridges extant and is noted for its extremely flat trajectory.