I would think anything would hurt at close range, but I doubt birdshot would incapacitate reliably.
Not a human like target, but today I was shooting at plastic pop bottles stuck in the snow with 7 1/2 shot ( federal bulk from walmart) at about 35 yards (turkey choke). I thought I was just a lousy shot because nothing seemed to be happening downrange. Walked down to check it out, and all the bottles were hit, and had shot in them that penetrated one wall of the bottle, but not the other. At similar range, 22s are all through and throughs. I suppose at personal defense distances, they would hit harder, but shooting pop bottles at 10 feet hust isn't that interesting
