Captain Pedantic shows us how to make a cool water bottle rocket pistol.

This looks great and all you will need is just common stuff and a bicycle pump for the launcher.
Just don't forget to take it when you go for a picnic on the beach.
I just wanted to advice you that take colored water instead of simple water as used by Captain Pedantic...!
Click Here for the detailed procedure.
Thanks: Captain Pedantic

Via: makezine