Originally Posted by therukh
I don't think recoil is going to be a problem with either a 9mm or a .556. Since your wife is very small, a long gun (carbine) may be a bit more difficult for her to shoot and maneuver in the home. Make sure you have her try a carbine on a range to see if any feel right to her. The 9mm handgun you're considering might well be the gun for her use in home defense. Having taught and worked with a number of females, one never knows which gun they will end up liking. They often choose something that I would never have predicted. What ever her choice, let her choose and let her practice until she feels comfortable with her choice. You can't go wrong with any of the choices you're mentioned in your initial post.
Originally Posted by John_Deer
With an equal amount of training any inexperienced shooter is going to handle a rifle far better than any handgun. It is much easier to line up the sights on a gun with a 16" or longer sight radius than a handgun with a sight radius of 6" or less.
If your female shooters are learning faster with a handgun you are the problem. Either you have poor instruction techniques or you don't know how to handle a rifle yourself. We have thousands of rifle owners that can't hit the broadside of a barn with open sights. In fact, so many people can't use iron sights it is hard to buy a rifle with open sights.
After rereading my post several times, I can't seem to find the logical transition from letting female shooters choose which firearm they like and then supporting that choice to learning faster with a handgun, poor instruction techniques & rifle shooters who can't seem to hit the broadside of a barn, from the inside - with the doors closed. Guess I need to learn to read between the lines a little better.