No, I don't rhink so. Your teeth would hurt. If your other hand is occupied, then the methods that's make sense is racking your pistol using other bodyparts that can do a gripping motion, just like your armpit, the back of your elbow, the back of your knee, or even in between your thighs (that include using your crotch) if you want some special "feel".
makkun said: other bodyparts that can do a gripping motion, just like your armpit, the back of your elbow, the back of your knee, or even in between your thighs
Or, in the case of this character, possibly in the cleavage.