We soon found the problem was that the ammo would get lost under the sofa or down the back of the radiator. I though it would be good to use something that was easy to obtain and that was a waste product, having thrown away hundreds of milk bottle tops I thought they would make a good projectile without hurting anyone - so the bottle top shooter was born!
Here in the UK all the milk bottle tops are approximately the same size, so any tops should fit the Bottle-Top-Shooter, hopefully they are the same in other parts of the world, but if not the design can easily be changed to suit other lids too.
The design of the shooter is in 8 pieces, which can be printed onto the flat surface of the MakerBot® machine, the parts will be assembled with machine screws and glued for extra strength.
I hope you like my idea, I have attached the step files, so feel free to print it, but please let me know how you get on, would love to see it in action!