When you say "near new"...
Who had it before you?
What modifications might they have made? EG: There is a mod to make this a stepless grinder - perhaps this has been done.
If I recall from when I had my Rocky, there was a screw in place somewhere that could stop the movement of the hopper, but mine certainly had a range of movement from less than 0 to greater than 30. Sounds like something has been done to it.