The current self defense rounds are designed to limit penetration in a soft target. You need to worry about the rounds that dont hit the soft target. Frangible's are supposed to break up when they hit a solid object like a wall. Some do and some dont. This link will take you to a site that does some honest testing. http://www.theboxotruth.com/
Don't miss. lol. Serious tho in all my research my ammo is focused on stopping the threat, not missing the target. I carry 180gr Gold dots when in the house and 165gr outside for potential glass penetration.
I would do my research on frangible ammo. The gelatin tests I saw were not adequate for self defense in my opinion. Really I have my doubts about solid copper ammo not going through an attacker. I shot a fat pine stump that stopped a backhoe with a 12 ga solid copper Brenneke slug. The slug split the stump enough for me to get the teeth of the bucket in the stump and finish splitting the stump. If I had not split the stump I would have dug an 8' deep hole before getting it out of the ground.
+1 for john_dear! As a medic I've seen all kinds of craziness after a round enters the body. You b surprised how often bone will change the trajectory of a bullet and make it a minor wound. Not mention heavy clothing.