I'm assuming you mean the scope tube needs correct level alignment in the scope rings....
I secure the rifle in a gun vise, and placing a level on the action ensure the gun is level.
I then place the level on the top turret and turn the scope in the rings until attaining perfect level, then torque the rings down.
MidwayUSA offers a Wheeler Engineering tool that facilitates what I just described for not too much money:
Now if the reticle isn't plumb inside the scope itself, it's time to send it back to the manufacturer.
XD-40 service, XD-9sc, member GeorgiaCarry.Org, National Rifle Association, Gun Owners of America, North American Hunting Club, Rocky Mountain Elk Foundation
Last edited by treehugger49; 07-31-2012 at 06:52 PM.