AllanSwann wrote: What he wants to do in the meantime, however, is simply allow each child to fire various guns at targets, starting with a BB gun, then 22, then shotgun. The mother wants the children to not fire guns at all until they have passed the course. The father has already had the youngest child shooting a BB gun and the boy has fired each weapon (even the shotgun, which apparently left a bruise on his upper right arm and led to this discussion and now, my decision). Any specific thoughts on this narrower question would be greatly appreciated.
I didn't handle guns myself until I was drafted into the army at 19 years of age. But my uncles, in the years immediately following World War II, spent much of their childhood finding American bombs gone astray, defusing them, and exploding their contents for fun. This got two of them started into successful careers as chemists, and nothing bad ever came off it. In other words, I have a fairly relaxed attitude about handling explosives, guns and other forms of deadly force, if the handlers know how to do it. I have the same attitude about handling cars. But the part about knowing how to handle them is critical.
With this in mind, my answer to you has two parts. First, in my opinion, it is irresponsible to let
anyone, especially a child, shoot a gun without thorough instruction in gun safety. Second, gun safety is not rocket science, nothing only anointed professionals can teach. It consists of a few common sense rules, and a habit of following them religiously. This habit cannot be acquired except by following it, and it requires someone who
wants to follow it. Therefore, I find that age is not the important issue. The important issues are, first, whether you know any grown-up who possesses some pedagogic talent, and who can be trusted to take gun safety seriously. Second, you have to have children you can trust to follow security precautions once they're taught to them. (I have seen five-year-olds I would trust, as well as twenty-five year olds whom I wouldn't.) If these conditions are met, you can have the grown-up instruct the children instead of having them attend this particular course. If one of those conditions is not met, forget about it until it is.
Finally, rebounding shotguns can give you bruises whether or not you are following safety precautions, so I don't know if this was the real reason for starting this discussion. For what it's worth, from reading between your lines, my impression is that this isn't
really about gun safety. This seems to be about the mother not wanting to make her children too comfortable with killing too early in their development. If so, that is a moral position which she whould have to argue out openly with the father. If they are too estranged to talk one-on-one about it, maybe you ought to moderate. Either way, if her concerns are really about moral basics, this discussion needs to happen now. Otherwise, she will eventually run out of technical reasons for slowing this particular process down, so will have to argue the moral point later with diminished standing.