A simple rubber band gun i made for the kids out of a piece of 19mm pvc electrical pipe ,some wire and rubber bands.
It can also shoot multiple rubber bands at the same time.
I started with a piece of pipe of 52cm ,but for more shooting power you could make it longer.
I made an extension piece which i can put on if i need more power.
I made a bend at 40cm ,if you don't have a spring bender ,it is also possible by filling it with sand.
Or leave it straight and make a wooden handle and put that on.
drill some holes all the way through 3cm apart.
i made the holes 4mm.
try to bend the wire like this and put it through the holes.
now bend the other end like in the photo.
the 4mm hole in the top of the gun might need some enlarging.
make the front of the gun look like this.
put on the rubber band for the trigger.