I own a bowtech justice 30 in draw at 60lb (dealer said 63 max). So now I am trying to select my gold tips for hunting> I am try to get as close to the IBO as possible 296-308 and they say 6 grain per inch, my guess is just the arrow shaft. But the problem is when on gold tips web site for my draw and pounds they say use the 5575 but the grains are 8.2 and the 3575 are 7.4. So I am not sure how to understand to differance in specs and what would work the best .