The physics are simple, the harder you push something out the front of your gun the harder it pushes back. I feel that you should shoot the largest caliber you can while still being accurate. Once you start flinching or being afraid of what will transpire with the pull of the trigger, it's time to throttle back. This is when misses and even poor wounds begin to occur on the animal. I lift alot of weights and stay in great shape so I shoot a 300Wby Mag, and can do so without feeling the effects (except on my ears). The harder the rifle is pushing back, the harder it is going to be hit. I also never complain about the recoil while I'm standing over a harvested animal. Just something to consider!!