I'm a southpaw and shoot accordingly, but...I most-likely started out right-eye dominant. Made for some fairly crappy shooting situations in my youth. Over time, I seem to have become cross-dominant. I do know that if I shoot a SXS, the left eye becomes the dominant one (something to do with that broad plain of the barrels?). If I happen to pick up an O/U then I seem to get some confusion with my right eye. I have learned to ignore that confusion for the most part, and single-tube weapons aren't a problem. It appears that my boy has exactly the opposite situation. I'm starting him as a lefty to (hopefully) avoid the problems I've experienced.