The Magic Stick

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
paragod
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Thu Oct 05, 2006 1:45 pm

Here is my first propane injected gun.


I used double valves and a guage so that I could meter my propane shot. The chamber is 4"x14", and is done in sch 40 and sch 80.

I used a 2" ball valve to vent the chamber, and have a built in bottle holder on the other side.

The barrel is 2"x5' and is threaded for quick change. (I am working on a golf ball barrel next)

I used a partial piece of 2" PVC instead of a project box so that it would "fit" better with the overall look of the gun.

My fan is powered by a 9 volt battery, and I am still using a grill ignitor, but have a stun gun on order.

You probably notice influence from several other guns posted here on the forums, and I would like to say thanks to all of those guys for their great designs. Most notably Gort's blue flame, Keith's ECL 1400, and whoever "invented" the serrated barrel end.

The metered propane definitely adds to cost! (this gun is ran somewhere in the $150 range)
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The serrated end and ports work great on the barrel, and look good too!
The serrated end and ports work great on the barrel, and look good too!
I preffered having a holder for my tank that allowed me to remove it quickly. I did bungie cord it in place so it couldn't slide out.
I preffered having a holder for my tank that allowed me to remove it quickly. I did bungie cord it in place so it couldn't slide out.
My trigger is in the right handle, which I will redesign when I go to the stun gun.
My trigger is in the right handle, which I will redesign when I go to the stun gun.
My propane hose is 200psi rated compressor hose. (I liked the yellow)
My propane hose is 200psi rated compressor hose. (I liked the yellow)
My spud chucker... Notice the fan switch in the left handle and the wire looms to clean up the overall look.
My spud chucker... Notice the fan switch in the left handle and the wire looms to clean up the overall look.
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MrCrowley
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Thu Oct 05, 2006 2:55 pm

woah, thats a nice looking gun, reminds me of keiths propane injected tennis ball launcher...once again great gun.
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experament_u2
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Thu Oct 05, 2006 5:55 pm

that is a mad ass gun with all the bits and bob's

i dont like the green tho its a bit plane

but an extremly good for a first time propane gun
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rna_duelers
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Thu Oct 05, 2006 6:25 pm

Yeh top gun mate,got any damage pics with that thing?Perhaps there should be soemthing to not make the green so dominating such as more yellow parts seeing as you like the colour so much.
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paragod
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Thu Oct 05, 2006 10:32 pm

Thanks! I'm gonna do some more paint work to it, including putting the name on in yellow, and probably switching all the wire loom out for yellow. I painted this one green because I had a basic hairspray gun that I used for years painted that way.
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killagorrila99
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Fri Oct 06, 2006 12:05 am

Very nice! Distance? Ammo? Weight? Do you have a sister? lol nah im not that desperate 8)
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sgort87
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Fri Oct 06, 2006 12:33 am

Oh nice man! I'm really happy to see other people using this design. I hope it's working out well for you. I know I love it. :P
paragod
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Fri Oct 06, 2006 6:37 am

The weather's been pretty nasty, and work has kept me from doing but a few firings, but I know that I put my first spud into the woods across just under 7 acres. I will addd to the post with some more specs once I get some better weather. Right now I'm just set up for taters and "shotgun" ammo (anything shot with wadding.) The gun is prettyheavy with the propan bottle and pieces parts. Once again, I will get some more specs and maybe a firing video shortly. Thanks!!!!
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mark.f
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Fri Oct 06, 2006 8:18 am

Although I'm probably going to regret it if you're gun beats mine... 8)

My gun is the only applicant for combustion in the SpudFiles contest. Would you like to enter?
paragod
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Sat Oct 07, 2006 6:19 am

thanks Mark. I sent my info to pimpman, so we will see what happens. I don't know how it will do being my first cannon, and pretty rough at that... no see through chambers or fancy boxes. Anyhow, we will see.
Viper
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Sat Oct 07, 2006 12:10 pm

nice gun. Just like everyone says add more to the paintjob. I am lucky that my uncle knows a guy who is an auto detailer. He always pulls through with a nice paintjob for my spudguns. I will probably put some pics and specs on my gun later this year.
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malman
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Thu Oct 26, 2006 4:06 pm

Nice Gun, Im yet to figure out how to make a propane gun, but from what I See on here thats a nice looking gun, Killer idea for the bottle holder!
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jjjd
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Wed Dec 20, 2006 3:17 pm

what do you do if the fan breaks?
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chartreusesnot
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Sat Jun 09, 2007 7:52 pm

Looks pretty damn cool, but wouldn't the ports on the side of the barrel provide an exit for the expanding air after the potato/projectile has passed rather than to push the projectile further?

on the other hand, the ports might evacuate air from in front of the projectile faster providing less resistence...
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A-98
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Sat Jun 09, 2007 8:05 pm

mmmkay, little bit on the dead side, but you asked a decent question.

the answer is : it mainly for cosmetic reasons, but it may add a bit preformance wise. on my one combustion gun i had a barrel like this and a normal one, and noticed no difference.

however, on large/conventional guns (e.g. artillary) it serves a purpose. when the projectile exits the barrel the rapidly expanding gasses propelling it fire out past it, and due to reasons that i dont care to explain nor fully understand myself, has the effect that the projectile is traveling backwards. the ports reduce this effect, adding to the preformance of the gun. pluss, it makes for a damn cool muzzle flash.
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