[Templar1396]

I'm a senior year mechanical engineer student mentoring my former high school trying to do these calculations.

so a few things, Drag is a function of v^2, i would say that unless you are using a large air cannon it is pretty much MOSTLY negligible

Coefficient of restitution will probably be the greatest loss of energy you will encounter

if you want to tackle this i would say, construct a free body diagram, do some energy calculations, maybe some work calculations. balance using Newtonian mechanics and then try to come up with something feasible.

Good luck, and remember to just have some fun