Fold thicker sections of paper into rectangular or "L" shapes to create the grip and shoulder rest. Glue these to the back of the barrel. The "Hack" (Firing Mechanism): Cut a small slot in the top of the barrel.
Stretch a from the front of the barrel back to the trigger mechanism. When you pull the trigger, it releases the rubber band (or a paper pellet pushed by the band).
These provide the tension for the firing mechanism. Scissors: To cut specific parts like the trigger and scope. Assembly Steps
Use black or camouflage construction paper for a more tactical appearance.
Create a "trigger" using a small paper lever or a folded hook.