7MM STW is a 8MM Rem mag case necked down to .284 bullet. The larger case inturn will create velocity, energy and Trajectory gains using the comparable .284 bullet. The actual gains will be approx 300fps faster/energy equating to less drop at the same ranges over the 7mm Rem Mag. For those who shoot 300plus yard they will notice a big gain in performance, for those shooting upto 300 yards while gains will still be seen it would not really lend itself as a huge benefit for these type situations. Basically flatter and more umf running the same .284 bullet and a great choice for long distance shooters who reloads!