I found this in the Kleck article I mentioned: Low as it is, even an 8% wounding rate is probably too high, both because of the censoring of less serious cases, which in this context would be cases without a wounding, and because the survey did not establish how Rs knew they had wounded someone. We suspect that in incidents where the offender left without being captured, some Rs remembered with favor" their marksmanship and assumed they had hit their adversaries. If 8.3% really hit their adversaries, and a total of 15.6% fired at their adversaries, this would imply a 53% (8.3/15.6) "incident hit rate," a level of combat marksmanship far exceeding that typically observed even among police officers. In a review of fifteen reports, police officers inflicted at least one gunshot wound on at least one adversary in 37% of the incidents in which they intentionally fired at someone.[78] A 53% hit rate would also be triple the 18% hit rate of criminals shooting at crime victims.[79] Therefore, we believe that even the rather modest 8.3% wounding rate we found is probably too high, and that typical DGUs are less serious or dramatic in their consequences than our data suggest. In any case, the 8.3% figure was produced by just seventeen sample cases in which Rs reported that they wounded an offender.
but it doesn't help debate-wise because it's all survey answers of gun owners. I was hoping for something more concrete.