You can go to a website called Huntersfriend.com and look under arrow selection . This is a great article that will explain everything you wanted to know about arrows and arrow flight. It will also help you pick out the right arrow.

I too had the same problem and I came to find out that my nock point was to low. I also found that I was not centered correctly. Once corrected my arrows fly true. Check out the website. Lots of info.