In photography circles in the US it is occasionally suggested put a gun (can be a flare gun) in the luggage as well -> it then has to be specially tracked and is supposedly looked after a lot better. No clue how much truth there is to that.
There certainly are additional declaration, inspection, and tracking requirements for firearms in checked luggage, so it might well be a cheap way to get extra insurance that your expensive camera gear ends up in the same place you do.
