This would be extremel hard to chart because most of the spine issues deal with forgiveness to the shooter.groups will get better but when talking minor differences it is hard to dfferentiate between what is the arrows fault and what is the shooters fault.



For me,I know that when I stay within the perfect spine range to marginally stiff range on my spine,according to my computer program,Archers Advantge.I shoot better scores ,on average than when I get way stiff to slightly underspined.I shoot my absolute best with arrows in the .420-.470 spine range and the .470 is better at distance and that is PERFECT spine according to my program.This may be a testiment to the fact that I need as much forgiveness as I can get.[]



I have a friend who has tested many thousands of arrows out of a shooting machine and as to his results,I can't say for sure but I know he swearsto having the perfect spine to slightly stiff.He tests and shoots arrows at 90 meters and is a world class coach and knows ALOT about this subject.