How do you have it mounted? The arm needs to be over the edge of the table - you can't just let the arm go down to flat - it has to travel beyond that to get a full stroke. It goes about 180° from it's fully "up" position.
Anyway, if that isn't causing the problem, mine was real easy to adjust - just loosen the nut, turn the screw 1/4 turn at a time, tighten nut. Repeat until you get what you want.
If you're crushing cases, you may have bent the rod as well. Or your brass might not be at the right elevation. Mine came set just right for .223, but if the springloaded rest is too high/low, the swaging pin will hit the bottom of the case & crush it instead of going into the primer pocket.
