I had the exact same problem. In fact I moved my rest left until it was way out of center and then had perfect bullet holes. After consulting folks here (Thanks Gibblet) I realized I was torqing the bow. I removed the grip plates on my Reflex Grizzly and "Voila" perfect bullet holes and perfect center shot. I have small hands and the grip was too large. I now need to rig up a set of grips, right now I just taped it up with electrical tape but it shots great.