7mm STW

The 7mm Shooting Times Westerner (aka 7mm STW) was developed by Layne Simpson in the late 1970s, although it wasn’t recognized by SAAMI until the mid ‘90s. (It is named after the magazine Simpson once contributed to.) The wildcat round is essentially an 8mm Rem Mag case necked down to seat a 7mm bullet. Bullet weights for this long-range hunting and competition cartridge typically range from 100 to 175 grains.