Be happy your son is a good shot, encourage that and maybe get him in the sport, something you can help him with.

Ammunition, try lots of brands. Mine really like the Bulk Federal. Just because a bullet is more expensive doesn't mean your gun will like it.

And then practice, practice, pratice.

My son is happy, although when we get done shooting he always says he's a terrible shot. I think he finds a real gun is quite different than his video games. I just tell him to keep practicing, it doesn't happen over night.