How to Make a Pen Gun Out of Mechanical Pencils & Rubber Bands

Unscrew the cap at the writing end of a mechanical pencil and pull all the parts out of the plastic cylinder. Discard the end cap, lead holding tip and spring.

Cut off the threaded section at the end of the writing end of the mechanical pencil with a pair of sharp scissors. Clean up the cut with medium grit sandpaper if the cut is not straight. A jagged barrel end may cause the pen gun to shoot the projectile at an angle.

Snip two rubber bands in half and align their cut ends on four different sides of the cut end of the mechanical pencil tube. Tape the ends of the rubber bands in place with duct tape. Use multiple layers of tape to keep the rubber bands from sliding out.

Remove all the lead from the inner cylinder by removing and replacing the eraser end. Slide the emptied inner cylinder back into the larger tube and align the intersection of the two rubber bands on the eraser.

Roll up a small wad of paper so it is approximately the size of a green pea. Stuff the ammunition into the cut end of the pen gun and stretch back the inner cylinder against the rubber bands. Aim the barrel of the mechanical pencil, using the side clip as a sight, and release the eraser end to send the papar wad flying.