Madsenshooter, the Shuster device has no presets, it is fully adjustable. You remove the locking Allen screw, turn the adjusting Allen screw fully closed, and open it until the gun fully functions. Then fine tune for the best group for the ammo you are using, then replace the locking screw. My M-1's best group at 100 yards, with Federal Gold Metal Match 168 grain bullets, was 5/8"x1/2", after adjusting the Schuster. It consistently shoots 3/4" or better.