Re: Adjusting Leupold STD base
As you adjust the rear windage screws, it should spin the front dovetail ever so slightly, but I cant see how it would affect the cant if you have leveled the reticle and tightend the rings.
How to use them? Loosen on side, and tighten the other while looking through the bore sight, until its lined up. It's designed as a "course" adjustment for initial mounting and bore sighting.
Hope that helps