Watching a visual guide, such as this YouTube tutorial for a Sawed-Off Shotgun , can help with tricky assembly parts. Would you prefer: A simple 5-minute design ? A full tutorial for the working model that shoots?
This version features a working loading mechanism and shoots paper projectiles using rubber bands. shotgun
Fold additional paper to create a small pump handle below the barrel and a handle/trigger area. 2. Working Paper Shotgun (Advanced) Watching a visual guide, such as this YouTube