You should be fine if carried in coach not cab. You're trouble would come when you pulled the piece. All kinds of laws govern when you may pull a weapon. If you used it to ward off a mouth attack, you're in trouble. Imminent threat to life, should be ok. To protect property? DON"T. Your life or the life of another is what you should be safe in doing. Someone breaks in the RV, they are inside and you kill them you should be ok. If they are outside the RV and no longer a threat you would be charged with murder.
There are also, pointing laws and assault laws to be concerned with. Keep the piece in the RV and you should be fine. Take it outside you may have legal trouble.