A dragoon revolver is more than adequate for a deer. Look around, people kill them with Remington replicas.
Yes, people do that. Yes, it can be done.
Hunters doing this kind of thing post about their success. I wonder, though, about how many failures and wounded deer there are that we don't read about. How often do people post about their misses?
Yes, one can flub a shot with a more powerful weapon as well, I know that; it just seems to me that opting for the minimum in a hunting situation is asking for trouble. One can do it but just because you can, doesn't mean that you should.