Gosh, two years ago! I haven't checked this stuff in a long time! Please forgive my tardiness!
The way the called-shot rule is intended to work is:
First you make a call: "I am going to try to shoot him in his gun hand."
Next, you roll to see if you hit at all. If you didn't even hit, then the called shot is moot. You missed completely.
Next, if you've rolled a hit, you roll on the location table. If you are shooting for the right hand, any number on the first die 3 and above means you've hit the hand.
The idea is that, although it is a more difficult shot, it would make it so you wouldn't accidentally shoot the person in the head or the foot.
Does that make sense?