I know someone here has tested this. Take 2 bows of the same make, set them up with an arrow at the same grain per pound of draw weight. Will the 40lb bow with the 400gn arrow shoot the same speed and trajectory as the 60lb bow with the 600gn arrow? Thanks for any feed back of actual results. Don
I don't think the "same" speed and trajectory due to differance in design, but close enough to switch back and forth. I have 4 bows ranging from 54 to 71# they are all set up with the same gpp arrows and I can shoot them all with no adjustment.
I spoke to my physics professor neighbor about this a few years ago and the answer is, all thing being the same, yes.
So, if bow bows are equally efficient, and the arrows used fly well, then it would take the same amount of energy to move each grain of weight which means that 40 pounds of energy pushing 10 times that many grains (400) would have the same trajectory as a 60 pound bow pushing 10 times as many grains (600).
Of course, there will be differences but the underlying idea that if you keep the pound to grains ratio the same the arrow will fly the same is true.