From what you describe, it seems normal. Having lived in areas of the country where hunting and gun ownership is the norm and other areas where it is considered a "high risk" behavior, it can be hard to tell what is going on in other families. IMO it is a good idea to talk openly with your child about gun safety.
If this is making you uncomfortable, you could try to interest him in the politics and personalities of key people in the war. Maybe including the conflicted feelings that many of the developers of weapons felt after their weapons were used in wars. I'm thinking of Nobel, Oppenheimer, Einstein, and Kalashnikov, all of who expressed regret for how their inventions were used.
