RE: Two weeks before gun season and my son is messing up in school!!
Sounds like he's learned exactly what amount of bad behaviour he can get away with in this system. You have to decide what level of bad behavour you will allow him to get away with.
Once you decide that you make it clear to him what the rules are and the consequences for breaking them. If hunting is the one thing that will get through to him, then do it. He has the rest of his life to hunt, and you with him, missing one day to teach a lesson is worth it.
Keep in mind though that you will need something once hunting season is over.