I'm a former CW re-enactor, with years of experience at both small and big events. After a guy with the 7th Virginia Infantry got shot accidentally at the huge 135th Anniversary Battle of Gettysburg re-enactment by a Frenchman who had flown over for the event without any training or experience and had fallen in with a less-than reputable Union cavalry unit, the hobby at large instituted wide-spread safety inspections before each scenario and required accountability on the part of battalion and brigade commanders.
Although there was a subsequent accident at Raymond, Mississippi, in which a guy got shot (through his testicles) with a .36 pistol round, the safety guidelines and intense weapons inspections have been quite successful since then. Obviously, at this event, the safety regime broke down, and someone got hurt. Both the event organizers and the the re-enactment community at large will suffer for it.
My guess is that it was some stupid cavalryman (infantry don't carry pistols--and they weren't close enough for a Confederate officer to have done it), who likes to target shoot his pistol at home and forgot that he had loaded it with a live round before coming to the event. That this guy's unit failed to properly inspect and pass the pistol is damning in the extreme. And he should NOT have been aiming directly at this Union cavalryman with the pistol, like it was a water gun.
The reenacters are saying the shot came from the confederate infantry side.
Time to find a new hobby! (among other things)
In the fledgling days of the North-South Skirmish Assn (1963) we were reenacting the 100th anniversary of Gettysburg. I was with the 3rd South Carolina that day and in the middle of a firefight the battle was halted.
The word was that a guy in my company had been hit in the shoulder and we all were sick with worry. It ended up that in some past shooting match a defective Minie ball had just the nose shot out, with the hollow base remaining. It was deduced that the constant firing of blanks (powder only, no wads) eventually loosened the base and out it went. We never found out who did it and I doubt that even the shooter would have been aware of it.
The guy had a half-moon cut in his uniform and a purple bruise as big as the palm of your hand. (When he grabbed his shoulder after being hit, the base fell into his hand.) We all kidded him that he could now say that he was shot at the Battle of Gettysburg and all felt that it was the best of bad luck as he could have been hit in the head.