How to Make a Rubber Band Pen Gun

Remove the stopper at the top of the pen, and the ink cartridge and the narrowed tip from the bottom of the pen. If you find it difficult to remove the ends, you can use the scissors, but be careful not to cut through the ink cartridge.

Snip the rubber band, creating one long strip.

Pass the rubber band over an open end of the pen, leaving a small pocket of slack about a centimeter deep, and run the two ends of the rubber band up the length of the pen.

Wrap the pen with tape until the rubber band is securely held in place.

Remove the ink cartridge from the narrowed pen tip, and put it into the pen tube.

Grasp the ink cartridge and pull back with the cartridge nestled in the rubber band pocket at the end of the pen.

Aim the pen at your target and release.