These pen guns use party poppers to fire off then pen head with a surprising amount of power. They're dangerous, so this is definitely a build it at your own risk project.

To build one of these, you'll need a standard Bic pen, a large paperclip, 2 party poppers, a bit of paper towel, and some tape.

If you like, you can use 1 or 3 party poppers instead, but with 1 the performance is pretty dismal, and at 3 you're seriously testing the pens structural integrity, so 2's probably the way to go.

The first thing you'll have to do is remove the head and ink tube from the pen.

It's not usually glued on or anything, so you should be able to just pull it off.

Next, straighten part of the paperclip out, heat it with a lighter, and use it to melt a hole about twice the width of the paper clip in the center of the pens plugged end.

The pen cap will eventually cover the hole, so it doesn't have to be pretty.

The only part we need from the party poppers is the pyrotechnic part, so either disassemble them and remove the popping elements, or, if your lazy like me, cut them open just in front of the grip part and GENTLY pull them out with pliers.

Once you've got the popping elements removed, cut the string off of one and tape the two tightly together with two or three layers of scotch tape. It's important that they be taped together tightly or the concussion from the first popper may not detonate the second.