I'd say Assault (2903.13 I think) is a good match. Specifically section B. Section A states the person must "knowingly" cause or attempt to cause harm. So I say section B, "No person shall recklessly cause serious physical harm to another". But that's a Felony 4 or 5. Does not require intent, but does require the prosecutor prove recklessness (that is, the guy knew of the risk of harm but did it anyway) Failing that I'd try for Negligent Assault, Misdemeanor 3. (2903.14 I think) "No person shall, using a deadly weapon or dangerous ordnance, negligently cause physical harm to another..." I can't believe a jury would think a shotgun, even shooting a shell with the pellets removed, into someone's mouth is NOT a deadly weapon or dangerous ordnance. It requires no proof of intent either, instead it only requires that the prosecutor show negligence (that the guy failed to recognized the risk, but a normal person *would* have) I'd prefer the felony conviction, though, to put him under weapons disability.