Public display of any gun, and I'm assuming most other weapons, even if they are only paintball/airsoft/replicas is illegal in most states. Also, even if you find some loophole and do do something stupid like this, all it takes is one person to call and tell the police that they feel threatened or in danger to make it illegal. It's also possible that you could violate other, seemingly unrelated laws doing something like this. The redcoat uniform and pretending to be a British soldier from the 1700's is fine, but leave the weapons at home.