Hey guys, I'm shooting a martin saber, 62# 29.5" draw beman ics hunter 400 spine @ 28.5" shaft. I shoot muzzy 3 blade 75 grain bh. My questions are, is that the correct shaft? At 75 grain is this to lite of an bh. I was told my arrows may be a little on the light side, that i might want to go with a heavier arrow or a heavier bh. I was also recommended to go with a four blade vs the 3 blade i have always used. I have seen you guys run numbers on here before. I would love to know the equation you use for this. Thanks guys any help would be greatly appreciated!