This is my breech loaded airsoft blowgun. I put it together in about 15-20 mins, so be expecting updates in the near future(later today).
Step 1: Materials
This is what you need(Duh)
1.)Pen barell(airsoft barell for over achievers)
2.)Highlighter cap that fits snugly around pen barell
3.)Leatherman, Multi-tool, whatever you want to call it
4.)Electrical tape(any kind will work, as long as it is about a half inch wide)
6.)Mp3 player(i used mine for lighting and a stand for the vid)
Step 2: Cut highlighter cap
Cut the cap about a half-inch from the open end.
I made this before the instructable, so i used a stunt double.
Step 3: Make loading hole
Drill or bore a hole into the side of the pen barell, anything that will make a hole big enough for a BB to fit through.
Step 4: Add breech
Tape up one end of the tube so the breech won't slide off and slip the breech on to the tube from the other end. on the un-taped side, crimp the barell A VERY SMALL AMOUNT, otherwise you'll break it like i did, only crimp it enough to stop the breech from coming off and so a bb can't roll back into your mouth.
Step 5: Celebrate!
Yay! You're done! Now all you have to do is put a BB in the hole and slide the breech over it then blow!
Here's the vid.