I would disagree with the arguments about hearing damage in regards to caliber selection. In the event of a self defense shooting your stress level is going to be very high. BAR (body alarm reaction) will be almost inevitable. BAR causes the body to undergo a stress induced physiological change which prepares the body for "fight of flight." Some of these changes include an elevated heart rate, tunnel vision, vasoconstriction, and auditory exclusion, among others. Its commonly reported among individuals who have defended themselves with their handgun that they never heard a single one of their shots. Yet at the same time, immediately after shooting, each piece of brass could be heard hitting the floor. Because of this, I think that its unnessesary to practice shooting without ear protection. The only thing thats going to do is cause hearing loss. During the stress of a gunfight, hearing loss is less of an issue.