This is a quick look at what optics can do for you if you plan to use a handgun for hunting. It is important to consider what you will be hunting, and what you want your limitations to be. Take a look at the photos below, and you can see how the sights on your pistol affect your accuracy, and your maximum effective hunting range.
The iron sights on the Single Six are clearly not good enough if I want to nail squirrels at 25 yards. However, this level of accuracy is fine if I want to be able to pop a coyote while I am out on a woods walk. This level of accuracy is also good enough for dealing with coons, possums, and skunks, if I hold my range to about fify feet.