As SK'er said, Make sure you straighten your shafts BEFORE tapering for your BH. If you use a hot melt glue to attach the heads, you can adjust alinement while the glue is still in a molten state.Test concentricity by spinning the arrow vertically with the point on a flat surface. Sometimes it helps to complete this process with a field tip attached, and then replacing it with the broad head.Spin test again. Check out the How To section of TG Make sure the spine weight of your arrow is correct for the length of your arrow, and weight of your BH or field point.