because "gun" sounds so violent.
This is a pump action device. The mini-marshmallow is placed in front fo the 1/2 inch pipe. The bottom pipe is pulled out, and the marshmallows get pushed by the outside air pressure (sucked, if you will) deep into the 1/2 inch pipe. The bottom pipe is then forced back in, and the marshmallows are launched forward.
- 2 feet 1/2-inch PVC (schedule 40 or 80) pipe
- 2 feet 2-inch PVC (schedule 40 or 80) pipe
- 2 feet 1 1/2 inch PVC (schedule 40 or 80) pipe
- 2 inch PVC connector sleave
- 2 inch to 1/2 inch adapter
- 2 1/2-inch right angle threaded bend
- small disk of cardboard
- duct tape
- 5 inches of thread
- PVC cement
- Cut out a piece of cardboard that is the same size as the 1 1/2 inch PVC's cross section. Use duct tape to firmly affix it to the end of the pipe. Wrap duct tape around the end until it is almost the same diameter as the 2 inch pipe. Apply glue to the tape (I used Gorilla Glue) and then wrap with yarn. It should make a snug fit into the pipe. Do the same a bit farther down. Repeat with yarn or use some self adhesive felt. I made snips in alternating sides so that it would lie flatter. Allow to dry.
- Dry fit the PVC pipes together using the model above. The small right angle fittings also come in slip fitting rather than thread. I prefer the thread because then I can take it apart.
- Place the thread across the 1/2 inch pipe between it and the right angle fitting to make sure that mini-marshmallows can't go all the way into the bent sections.
- Once everything is working, use PVC cement to connect the joints.
I didn't come up with this design, I first saw it here. I just adopted it from Nerf darts to mini-marshmallows.