The Great Potato Cannon

A homemade potato gun that is aerosol powered and easily constructed with parts from your local hardware store for under $50 !!

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Step 1: Parts and Materials

It is a good idea to use schedule 80 PVC for your project.

For this project I used 4" PVC for the chamber and 2" PVC for the barrel. These pipe sizes can be changed based on availability.
Other important pieces are the :
4" cleanout with cap (Top right).
4" to 2" reducing coupling (Top Left).
4" x 4" x 2" coupling w/ sweep 90' (Middle)
2" cap (middle right)
PVC cleaner and cement

Not pictured : a BBQ grill igniter (pushbutton type)

Step 2: Chamber Assembly

Using your 4x4x2 and cleanout test fit the parts together and prep the PVC cleaners and glue. Cleaning and gluing are important because the potato gun builds quite a bit of pressure when it fires. (Pictures 1 & 2)

The cleanout and cap will fit right into the 4x4x2 coupling.The 2" sweep should curve away from the cleanout when it is installed. glue these pieces together and you have created the handle and gas chamber. The cleanout will be where we fill the gun with hair spray. (picture 3)

Next step is to add a 2" piece about 5" long to the sweep. Picture 4 is an example of how not to cut PVC (Ha ha ha) Picture 5 shows the 2" piece being inserted into the sweep.

Picture 7 shows installing the 2" piece into the sweep and putting the 2" cap on the end. This 2" cap will serve as the trigger assembly.

Picture 8 & 9 illustrate cutting a 12" piece of 4" pipe and inserting it into the coupling. The chamber is almost complete.x

Step 3: Trigger Assembly

Using a 3/4" paddle bit, drill a hole in the end of the cap. This hole will allow the BBQ igniter to fit perfectly into the cap.

Picture 4 & 5 show the right area for the ends of the igniter to be. It's a good idea to try and keep the sparking ends of the ignitor out of the chamber, Spraying these pieces with hairspray might affect the spark.

As an atempt at a better seal I wrapped all connections with duct tape!

Step 4: Barrel Assembly

Attach the reducing coupling to the 4" chamber. This is where the barrel attaches to the chamber. Next cut the 2" at about 3' and secure it to the reducing coupling.

Step 5: Loading the TATER'

With an item to use as a ramrod, measure the distance of your barrel and mark the rod so the potato remains in the barrel and does not fall into the chamber.

Select a potato that fill completely fill the barrel, use the ramrod to shove the potato down the barrel and you are ready for the fuel.

Step 6: FUEL !!!!!!!!!!!!!!!!!!!

Opening the cleanout spray the hairspray into the chamber for about 3 - 5 seconds, (Iwould start on the shorter side and work your way up.) cap the cleanout and BOOM !!!!!

Step 7: A Word of Caution!

If you do not follow the PVC Glue manuf. directions about waiting the 24 hours for the glue to dry there is a possibility that the fumes from the glue would be enough to lob a potato through your soffit on your backporch. BE CAREFUL.

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    67 Discussions


    6 years ago on Introduction

    Don't you guys worry about the chamber exploding in these potato guns? I've had the cap go flying off my potato gun before.


    6 years ago on Introduction

    Making mine soon. Thanks for the instructable!!!

    @ The video posted: Your going to want to put a screw through your barrel at the neck so you CANT shove the potato into the chamber DUH. Don't use a BBQ lighter there garbage and don't always ensure a fire. Use a lantern igniter. They don't fail. Sand the tip of your barrel and make it sharper to allow for the potatoes to enter easier. I added a guitar like strap to support the weight of the gun and to make it easier when twisting the lantern igniter. The best spray fuel is Static Guard. It will make those potatoes scream. Ive made plenty of these and done my research. Trial and error. Hope i helped others.

    3 replies

    Reply 6 years ago on Introduction

    Great advice. I'm about to make my own as well and from your suggestion going to go with the lantern ligniter and the strap. Going to be epic if it all works. Thanks again!


    Reply 10 years ago on Introduction

    Using a gun I had built previously with close to the same specifications, and ether as the fuel, we shot a potato 2700ft roughly. Measured it with a wheel tape. I live in a very small town and only about ten people total live here so we just shot down the old highway.


    Reply 10 years ago on Introduction

    i am sorry for calling you out on that but that is almost impossible unless you were using highly combustible fuels such as acetylene. and if you were trying to use a fuel that powerful with a pvc cannon you are not the brightest individual. you must be mistaken trust me i know


    Reply 8 years ago on Introduction

    I was getting around 800m using propane as fuel. the gun was at least double the size of the one in this build. gas chamber was 5ft x 6" and the barrell was around 9ft long made from stainless steel. I also had an oxygen tank to provide the proper fuel air ratio as well. I think it's easily possible to get well over a km with a well designed potato gun with the right wind and angle.

    A minimum of at least a hundred yards, I have not yet tried to acurately measure the total distance. I know that the distance varies by the amount of fuel used, BUT IF YOU TRY BE CAREFUL !!!!


    8 years ago on Introduction

    I found propane to be by far the best fuel, it doesn't leave stick residue on the sides of the chamber, I tubed a small home kit with oxygen and propane bottles, to eliminate the need to air out the chamber. I also find that if you gas up the chamber before pushing the potato down it compresses the gas inside and makes for a bigger bang. Ether or "liquid fire" works awesome as well.


    9 years ago on Introduction

     i couldnt find 4" pvc so i had to use abs and i still only went 3 inches....i think 4 inches is to big


    9 years ago on Introduction

    Hey is there anyway to make a thinner barrel and still have it work? if there is, is it possible to make a homeade rpg projectile to shoot out of it?

    1 reply

     A thinner barrel should not be a problem........based on the availability of your parts........  You would just need a different sized reducing coupling..

    I was just discussing the idea of different ammo the other day at work with my buddy......
    He told me that he always uses shop rags to form a "wad" similar to muzzleloading rifle. This enables you to use anything smaller than your barrel for a projectile. (ie; golf balls)

    GOOD LUCK!!!!!!!!


    9 years ago on Introduction

    where did you get schedule 80 pvc pipe from i have only ever heard of schedule 40 and thats the thickest i have seen and will schedule 40 work