[header] How to build an airsoft gun out of household objects [title] Drill 2 holes in a small container. [step] An old pill bottle, a film container, a plastic bottle of coca-cola, whatever you have lying around (with a lid! ) will do. Be sure to wash it first, though; you'll be putting the side of the bottle in your mouth. 
[substeps] One hole needs to be centered on the bottom and the other centered on the side. A 5/16 " drill bit is best for a standard pen, but it can vary.