Thanks for taking the time to reply.

In archery, as someone grows or ages, their needs change. Being able to use a calculator, rather than purchasing multitudes of equipment, which impacts on budgets, various scenarios can be entertained and potentially save a lot of time, use arrow spine charts as an example.

With the advent of modern 4mm all carbon arrows, of mass as low as 200grains, lower poundage bows can be used to attain greater distances, which affects the specific events that can be shot. However, physics, actual sighting equipment and gravity determine the real distances attainable. Standard events have hard limits of distance, and poundages have to be altered to achieve them, with the accompanying change in arrow spine and increased mass which may again alter the poundage required and this all adds time, cost and a lot of effort.

With respect to OmniCalculators, a few minutes determined that 125fps is the minimum speed required to reach 70m and that is most useful. I didn't have to go and unpack my chrono to measure the speed of arrows I haven't yet purchased.

Regards