There are several good recoil calculators on the net, inclduing the one here: http://www.rfgc.org/reload/recoil_calc.htm (For others, just google "recoil calculator".)

You plug in the relevant info (velocity, shot weight, etc.) and it tells you the recoil.

Of course, these do not calculate "felt" recoil, but assuming the same gun the difference in felt recoil should be directly proportionate to the actual recoil.