6mm Cannon




Introduction: 6mm Cannon

This is a 6mm mini-cannon made out of an old airsoft gun barrel. The tissue is used as a wadding to make a good seal for the expanding gases which allows for higher projectile velocities. The metal ram-rod is an old wire coat hanger, it allows you to ram the wadding into the barrel as well as clear the leftover firecracker debris. The pipe cleaner is to ensure a clean barrel for the next shot - maintaining a clean barrel is a good thing to do. This shoots airsoft bbs, or anything 6mm in diameter.

Explanation for the picture with the cans: It went through four cans with no sign of "stopping". I could test it with more cans however I fear that with added cans increase the chance of the bb diverging from its original trajectory.

Since I made this instructable after building it I will do my best to explain how to build one yourself.

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Step 1: Materials

The first thing you need to do is gather the required materials.

• Airsoft barrel or some other metal tube. (Must not have thin walls!)
• Metal piece (The piece I had was cylindrical at the base and a round ball at the top with a hole through the entire piece)
• Small blocks of wood
• Files
• Drill and bits
• Band saw
• Hammer
• Plastic staples or some similar bracket
• Epoxy or high-strength glue (JB weld perhaps?)
• Wire coat hanger
• Pipe cleaner (optional, but its a good idea to keep a clean barrel!)
• Firecrackers and ammunition
• Tissues

Step 2: Construction

1.) Prep the barrel.

The first thing you want to do is prepare the barrel to shoot things. This requires finding a metal piece slightly bigger than the inside diameter of the barrel with a hole through the center. After this is found you have to hammer it into one end of the barrel then hammer a small lip over it to keep it from slipping out. Feel free to shine the barrel in any way you choose.

2.) Making the base

The best way to do this is to find a drill bit the same size as the outside diameter of your barrel. Use this to drill a hole through the block lengthwise at an angle you want. After this is complete cut the block down the center of the hole so it comes out as a semi-triangular piece of wood with a uniform groove down the middle.

Next, epoxy the barrel into the groove and place this entire upper assembly onto a larger block of wood (this larger block acts as a base). Now hammer your plastic staples so that it holds the barrel snug in the grove and secures the small block of wood to the larger.You may need to file down your staples so that it can form a snug fit. Be careful! If you hammer the staples down too much or miss and hit the barrel you risk deforming/damaging the barrel!

Now for the finishing touches. Use a bit of epoxy at the very back of the barrel to prevent it from sliding back after each shot (Yes this small cannon has recoil!). Feel free to stain or finish the wood and shine the barrel.

3.) Shooting your cannon

To shoot your cannon place a firecracker into the barrel fuse down and shake until the fuse comes through the hole. Next, make a small ball out of tissue and use your ram-rod to push that into the barrel. Be sure to pack the tissue nice and tight into the barrel for maximum projectile velocities! Finally place an airsoft bb or similar 6mm ammunition into the barrel. You are now ready to shoot! Get a match and light 'er up!

CAUTION: Though this is a small device it shoots projectiles at very high velocities! Be sure to shoot in a safe direction free of people, animals, and anything you don't wish to shoot!

Be safe: wear your eye and ear protection!

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    13 Discussions


    I cant get any Firecrackers to fit into a 6mm barrel, I've tried all the types I could get my hands on.


    Reply 4 years ago

    You can take black powder and make your own but I would advise standing back about five feet and being in a well ventilated area as the smoke and gases it puts off can be harmful.


    7 years ago on Step 2

    Where can I get a small metal piece that is slightly bigger than 6mm and with a hole in it? What did you use?


    8 years ago on Introduction

    I got some great inspiration from this and it worked great! I used phantoms Hydro-crackers (TON of kick to em) and I closed the one end so it was just small enough to get the wick through it. I had it for about 2 months, and today I got the "great" idea to take apart one of their strobing ground blooms and pour all of the powder down the tube (after running a wick through the end) and I wanted to see what it would do. The few other smaller fireworks I took apart just shot flames out, so I figured it'd just shoot flames out of it... I'm sure it would've if I hadn't firmly packed the entire tube with the powder... Thankfully I decided to duck around a corner right after lighting it... the explosion was awesome. The first image is the finished project and the second two are the aftermath.


    9 years ago on Introduction

    this thing is AMAZING i made one and it shot clear through a 4 foot snow bank


    Reply 9 years ago on Introduction

    Thanks, be safe though, this thing is mighty powerful!


    Reply 9 years ago on Introduction

    Cool! Do you have any pictures of it?


    Reply 9 years ago on Introduction

    sorry i made it a long time ago but it was a plastic tube rapped in duck tape