If you look at the formula for KE(Ke=mv2).It's obvious that speed has twice the effect on kinetic energy than weight.However you also have to consider monentum which is how fast an object loses it's energy when it meets resistance.All things being equal I would like to shoot a 600 grain arrow 300 fps if I could.Since that's not going to happen I like to shoot an arrow aound 6.5-7.0 grains per pound.This to me is a good comprimize between speed and weight.Now if I'm hunting hogs in heavy cover i might go alittle heavier with a good cut on contact head.For antelpoe on the prairie I'd shoot 5 grains for maximum trajectory.For a good all around set up the above weight works for me.

CB

WHACKEM N STACKEM