I'm making a short pilot for a superhero web series with our filmmaking club at my university. We're pretty early in preproduction, just about to lock the script. We have a few scenes where a mugger tries to rob people at gunpoint. Unfortunately, we can't change it to a knife or something because it's important to the plot that it's a gun.
I helped shoot a gunfight in a forest preserve once, and we got the patrol called on us, so I can only assume that in urban Cleveland we'll get busted before we can film what we need.
I was thinking the solution could be to let the police know beforehand that a prop gun is going to be out, and also maybe have a couple people hold up signs when the gun is out saying "WE ARE FILMING A MUGGING SCENE. THE GUN IS A PROP" or something like that.
I don't know how much filmmaking permits would be, but I'm assuming it would be prohibitively expensive.
Does anyone have any suggestions?