Carrying prop weapons on the bus?

I'm going to a convention and the one mode of transportation is by my town's bus system... but I'm not sure about it, because I'll be dressing up.

My costume needs me to carry around a hunting rifle, and NO I won't be carrying around a REAL gun. I made one out of a long wrapping paper roll, paper, a toothpaste box and TONS of masking tape... I've painted it black and brown (to look like wood) and it turned out really good (for my first time making a prop) so that its almost "real size" and I'

Here's the thing... my costume is very minimal... that's why I need the gun... without the gun I just look kinda preppy with maybe a fancy skirt... I'm worried people will think I'm crazy and call the cops...