I have a 12 gauge Ultra Slugger shotgun and just had a new Bushnell Trophy 1.75x4 scope mounted and bore sighted at my local Dick's sports. I have not had a chance to take it to the range yet but when I look through the scope at the lowest magnification I can make out the barrel and the vertical crosshairs on the scope do not appear to be centered over the barrel. They are slightly to the right of the barrel. Is this normal? I have also heard about lapping scope rings, I have never done this in the past is it necessary?