How to Make a Large Bore Vacuum Cannon
 
In this video I show how to make a large vacuum cannon with a 4 inch bore. Vacuum cannons are a classic science experiment used to demonstrate atmospheric pressure, though very rarely are they made as large as this. My ammunition is 3 inch PVC end caps, and atmospheric pressure is the only force responsible for firing them. See my earlier video for how to build a manual vacuum pump: https://youtu.be/UkPLu6mgdWA