Just finished a 60 in long bow and was shooting through the chrono and found something weird or maybe not that weird.
Bow specs 60 r/d design 55.5 @ 28.75 my draw
Arrow 1GT 55/77 trad cut to 30.5 w/225 up front total weight 562
5 arrows shot ave. 180 fps 178 to 182 so pretty consistent.
Arrow 2 CE Heritage 350 cut to 30.5 w/175 up front total weight 598. 5 shot string ave 187 185 to 190
Could this be because the CE is better matched to the bow than the GT. Got the same results more than once. Is the GT compressing per say causing the energy loss.
I believe the GT 5575's are spined to 400, so the CE Heritages are stiffer out of the box. In addition, you are adding more weight up front to the GT's, further weakening the spine. So the GT's would necessarily have to bend more when shot out of the same bow than the CE's. It takes some energy to bend the arrow that is not available to drive it forward. Evidently the speed lost to bending the GT is not made up by the speed gained by lighter weight of the GT, leading to a higher overall speed for the CE.
That doesn't necessarily mean that the CE is a better arrow for your setup. That would have to be determined by tuning.
Which one flew the best? That would be the determining factor for me.