As the Rev said more or less the spine of the arrow and foc will be the only thing you will see. Unless the foc goes down to low or the spine is to soft out of the bow. I have shot many arrows in weight, with different weight heads from 85-125 with the same "stiff" arrow and hit in the same spot at 40yds but at 50yds the group started to spread. I tried this with little shafts and got real bad results.