I've got one of the "so-called" Confederate Navy's and it's probably one of my favorite guns. I load 16gr 3f Goex with a corn meal filler to bring the ball up to the end of the chamber. Regarding hunting with it...that depends upon the range. As stated above, if you can stick it in his ear it'll work.
I haven't chronographed the brassy yet, but I think I'll give it a little higher priority. As an example though, my '60 Sheriff's model loaded with 30gr 3f Goex chronographs out at an average muzzle velocity of 787 fps with an impact energy of 193 ft. lbs. with a 140gr round ball. Of course this is at about 15 feet which is where the Chrony resides.
A dead on "kill shot" on a whitetail would work, but you better be more adept at hitting what yer aiming at than me.
Have fun with it though, they are addicting, at least that's what my wife told me when she said I couldn't buy another gun until April.