Spin test, broad head and vane alignment, rest contact , and a well tuned bow. Depending on your arrows and set up you might not ever get your BH and FT to hit the same spot. Your forward of center on the arrow changes by a bit once you screw on a longer tip into the end of the arrow which then causes a different flight pattern.If your BH shoot a consistent group then they are tuned the same you might just haveto make a slight adjust on your sight.