According to Rick Welch, there are two relatively simple ways to move your arrows from one side to center - either cant the bow, which seems to be working for you, or get a lighter spined arrow. For a LH shooter, shooting to the right can be caused by a too stiff arrow or by the fact that with the bow vertical you're hitting where you're aiming, just not where you think you're looking 'cause the riser is cutting off more of your sight picture than you realize.