Gear Rifles - design assistance requested

[Anthony]

Originally Posted by Varyon

The issue is... I don't know how to calculate this for my gear rifles. I can work out the recoil energy for them, provided I ignore the secondary recoil from accelerating the working fluid (I think this can be done safely in this case). After messing with the math a bit*, it looks like the recoil energy is equal to the muzzle energy multiplied by the mass of the bullet, divided by the mass of the rifle - Rk = Bk*Bm/Rm. But that gives me energy, and the values I have to work with to set "Is this wieldable?" are in terms of force.

If it's expressed in units of force it's almost certainly in error, the peak instantaneous force for a .223 rifle is in excess of 2,000 lb and that's a relatively low recoil rifle. I suspect the sources you were looking at were actually giving foot-pounds, which is a unit of energy.