Badass Combustion Cannon - 2.7m long, 20cm chamber and 11cm barrel.

So here goes. its been a while since i`ve written anything on my website but here is my latest cannon.

I built it several months ago so its nothing really new. Now I will explain how i built it ...

 Just some pictures from front and back of the cannon. It took quiet a lot of work and adjustments before i was pleased. And thanks to cL0n I got alot of the parts for free. *Shhhh, dont tell anyone*


Yepp, well i used 2x 90 degree "110mm" pipes. 250cm of 110mm pp pipe as barrel. 80cm of 200mm pvc pipe as the combustion chamber. 2x 200mm muffs and 2 transitions to get from 110mm to 200mm (from 200 to 160mm, then from 160 to 110mm). And one end lid for the 200mm.

I also used 125mm pvc pipe to make the pipe that the barrel runs through and the handles are stuck to.

All pipes are screwed together. no glue on the pipes. As ventilation holes.. 

                                            I drilled a hole through the end lid and one through the on of the transitions and then glued a bottleneck in the holes. i cut a bottle right under the neck of the end of the bottle so the neck would work as a stop so the hole thing wouldnt just fly out once i ignite the cannon. and the glue was to make it airtight.

The ignition is a barbeque electric spark thing with one aa or aaa batteri that i bought from Sterling Products on search for "electronic spark igniter" it makes a spark 2 cm long. i got 3 spark points on my cannon to make a batter effect out of the ignition. dont know if it works better but it made me feel good to make 3 sparks. I use Hairspray as the gas. I also made a safety switch so i haft to hold 2 switch in to ignite the cannon.

And i also got tons of extra support struts because the barrel moved back and forth the first times i tried the cannon. I havent tried to hold the cannon up from the ground and shoot yet because it will most likely recoil me to the ground. (thanks to grg for testing that out :P)

Oh yeah the ammo is 800 gr. canned fishballs :)

So to break down what i used on my cannon:


  • 2 x 90 degree (110 mm pp) - bends (connects the barrel to the chamber, a easy way to make the cannon more compact.
  • 2 x 25 cm long (125 mm pvc) - pipes (used to run the barrel through and for attaching the handles)
  • 250 cm (110 mm pp) - pipe (barrel)
  • 90 cm (200 mm pvc) - pipe (combustion chamber)
  • 1 x (200 mm - 160 mm pp) - transition (to downsize from chamber (200mm) to (160mm)
  • 1 x (160 mm - 110 mm pp) - transition (to downsize from 200-160 transition to 110mm barrel)
  • 1 x (200 mm) - ters / end cap (to close the cannon in one end so the explotion goes the other way) 
  • 2 x (200 mm pp) - double muff (to connect the ters / end cap to the combustion chamber) and one to connect the 200-160 mm transition to the combustion chamber.
  • 1 x (110 mm pp) - double muff (my fan patent to attach to the end of the barrel each time you need to ventilate. a fan inside the chamber will get destroyed with such a big cannon (if you where to put it across the width of the combustion chamber) i have one fan inside my chamber but it is just attached flat to the chamber wall to mix the gas.
  • 2 x (90 mm) - pc fans (brushless fans.. that means it makes no spark which could ignite the combustion gas)
  • I used alot of hose clamps. they are a nice way to attach stuff to the cannon without weakening the construction with screws all over the place. i used 2 clamps on each 25 cm long pipe that i run the barrel through and also have handles attached to. and i also used clamps to attach stuff like the spark igniter, extra support struts and a protection thing along the side of the cannon.
  • I used somewhere between 50 and 100 (20 mm) screws with threads all the way to attach all the pipes together. i used somewhere around 10-15 screws on each transition.
  • 2 x bottle necks and corks as wentilation holes. drilled a 25 mm hole (or somewhere around there) and glued the bottle neck in the hole from the inside of the cannon so it wouldnt get blown out when i ignite the cannon.
  • 1 x Electronic Spark Igniter from (Sterling Products) that used 1 x AAA battery.
  • 2 x 9 volt batteries serie connected together as one to drive the fan faster.
  • 2 x (32 mm pp) - (handles) .. one where cut to fit inside one of the 125 mm pvc pipes (front) that makes the highest points on the cannon. the handle i have at the back of the cannon is run through one side (the side pointing forward) of the 125 pipe and then screwed in place at the back. the handle goes along the cannon. the first handle is attached across the cannon (check out pictures) i made the handles stronger by sawing a piece of a wood handle that fitted inside the 32 mm pipes.
  • 2 x switches, one as main firing button and the other one as a safety switch. both buttons must be held down to fire the cannon. the safety switch is hard to accidently push because of the location. (attached down inside the frontmost 125 mm pipe.
  • 2-3 m with cable to connect all spark points and spark igniter and fans. the spark igniter needs a good isolated wire so the sparks dont jump from wire to wire. i dug up some info on how to stop sparks from jumping from wire to wire and construction foam is supposed to isolate pretty good. i tired it on a medium cannon and it seems to work. 
  • Struts / bars with thread to strengthen the end cap / ters (see picture) and to hold the barrel in place. this is combined with 90 degree brackets and nuts. i also used perforated strips to make the 90 degree brackets stronger. (you just haft to try and figure it out from my pictures because its so hard to explain :D)
  • Hairspray - Cheri L'Amour 400ml Extra Firm Hold (cheap thing from a "all-sorts-of-things-store"


  • Battery powered drill
  • Glue gun
  • 32 mm drill
  • 25 mm drill for ventilation holes.
  • Jiggsaw (to make the 2 x 125 mm pipes fit the chamber and the holes for the barrel)
  • Knife (to adjust every hole that i couldnt get to fit with other tools)

Cheers Thomas