The Hater Cannon :: My First Spud Gun

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.
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Woody
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Sun Nov 15, 2009 9:48 am

Pretty good for a first gun. Wish I had this site when I made my first. Although I agree with everyone else here. The range claim you made is ridiculous. I have a similar cannon to yours as far as dimensions. Even shooting frozen spuds I've only manages to reach as far about 750 ft. I've gone further than that, but further than I can record and those were shooting arrows. It is a nice gun though, I'll give you that.
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Technician1002
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Sun Nov 15, 2009 10:12 am

This is a special device that can only be found in power plants, my dad works for a nuclear company so I got it thru him. i will show no pics of it.
Regardless of what it is, it still has to deal with the laws of physics. If it is a valve, they have an opening time, and orifice, and a coeficient of effeciency. None can exceed 100%. If it's an explosive, don't post it here. If it's a very dense cylinder with fins, it's a missle. Tennis balls on 100, 150, or 200 PSI simply don't make a half mile in distance unless you are launching at a really high elevation for thin atmosphere.

What elevation are you? If you are operating at above 20,000 feet I may reconsider the claim.
oh, and I use about 175 psi. and yea, i know someone is gonna call me out on that, but i really don't care.
Give us a projectile weight, density, velocity and we can work the physics if the launch exceeds 100 % of the energy given. If it puts out more energy than it is given, then it's easy and a no brainer to call BS along with over unity motors and perpetual motion. Give us something believable that will work with the laws of physics and we will go from there.
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Ragnarok
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Sun Nov 15, 2009 10:38 am

@Tech: Don't bother getting into discussion. If these guys want to hide under a pile of BS, then the joke's on them.
We can see it's a pile of cow turd, we can smell it's a pile of cow turd, and so they just look like idiots for pretending it's chocolate mousse and swimming in it.

The best idea here is not to get near enough that we risk falling in with them... or in fact, being close enough that they could hit us if they try to throw it.
Does that thing kinda look like a big cat to you?
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rp181
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Sun Nov 15, 2009 11:00 am

This thread made me laugh. Don't be stupid, the DOE doesn't have to obey physics!

BTW rag: I bet 2-3 months.
Last edited by rp181 on Sun Nov 15, 2009 12:33 pm, edited 1 time in total.
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Technician1002
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Sun Nov 15, 2009 12:29 pm

Ragnarok wrote:@Tech: Don't bother getting into discussion. If these guys want to hide under a pile of BS, then the joke's on them.
I simply let them know BS walks. Verifiable facts are checked for accuracy. When they don't, it's easily seen as the BS it is.

I don't claim over 100% cof on my valve and I post actual measurements, unlike those guys. We all know about how far 200 PSI will toss a spud or a tennis ball and roughly how much more power is required to double that. The claims at about 5X that is well out of the realm of believable as the power is not linear with the range. Getting over a magnitude of power increase would put the launch near Mach 2, which they did not claim. We know how many attempts at Mach 1 with large projectiles failed. Doubling that speed on less than 200 PSI air quickly trips the BS meter hard over.
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Sun Nov 15, 2009 3:16 pm

OK you guys flamed this up enough, if the auther want's to make any corrections it should be done promptly if not no point in carring this out into a flame war...
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