Turning the nock???
For the past two years when I shoot my broadheads I always use NEW arrows. Anyhow I have to turn my arrows to a different odd feather(sometimes) to get them to be dead center. It is not a big deal I like that I can do it, but what causes this?? Differnet spine? Like I said it aint nothing for me to drill the center out with every arrow once I turn the arrow just curious??