Overkill?

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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pizlo
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Tue Jun 24, 2008 7:02 pm

Wow guys, why can't we just say, your chamber is too big, and won't yield much more power than a smaller one. He never asked about going supersonic, and now we turned a help me post into an argument about the validity of a supersonic gun. Metal is often a but more expensive, but as members have proven threaded fightings and pipe are reusable. For a first gun, just try things, have fun with it, then read the forums every day for 2 months. At the end of that time you'll understand a LOT about potato guns, and probably have a dozen designs that you're ready to build, but you gotta start somewhere.
Good luck!
sandman
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Tue Jun 24, 2008 7:02 pm

evacuated barrel might help a little, but i dont think it could be pulled off in 2" Sch 40, but my 2" sch 80 is rated to 400 psi
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magnum9987
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Tue Jun 24, 2008 7:41 pm

Ok, lets make a new approach:

HAs anyone chronograph their gun to get subsonic speeds?
What materials where used to what dimension?
http://www.spudfiles.com/forums/viewtop ... Revolution in the absolute is not initiated by swords, guns, and bullets, but by words-
The New RobesPierre
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DYI
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Tue Jun 24, 2008 8:26 pm

It amazes me how people forget about Dongfang's supersonic shot with a gun made of thin-walled plastic drainpipe. The speed of sound in a combustion launcher's chamber is high enough, you just need to make it really big with a relatively light projectile.

People have chronied their spudguns at supersonic speeds. Actually, most of the supersonic shots have been with plastic launchers - metal construction didn't gain popularity in this hobby until very recently.

My ME20H-41 can shoot supersonic, as can Killjoy's FEAR, Dumbascii's Taternator II, and one of Spudinator's hybrids (can't remember what it was called). Larda's ETG could do over Mach 3 with a light projectile, but I'm assuming that you don't have thousands of dollars to invest in capacitors, and it isn't what most people would think of as a "spudgun" anyway.
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
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magnum9987
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Fri Jul 04, 2008 11:15 am

What schedule .5in pipe would be best for a marble.
http://www.spudfiles.com/forums/viewtop ... Revolution in the absolute is not initiated by swords, guns, and bullets, but by words-
The New RobesPierre
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bigbob12345
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Fri Jul 04, 2008 11:21 am

magnum9987 wrote:What schedule .5in pipe would be best for a marble.

type M copper is best
but if you have small marbles then sch40pvc works, and if you have big marbles then 1/2in sdr21 works good.
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SpudFarm
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Fri Jul 04, 2008 11:30 am

magnum9987 wrote:Ok, lets make a new approach:

HAs anyone chronograph their gun to get subsonic speeds?
What materials where used to what dimension?
i did with my hybrid.
look in the showcase section, the first hybrid i posted.
"Made in France"
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magnum9987
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Fri Jul 04, 2008 12:20 pm

Is the fit tight, bigbob?
http://www.spudfiles.com/forums/viewtop ... Revolution in the absolute is not initiated by swords, guns, and bullets, but by words-
The New RobesPierre
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