two questions

[spudkilla]

ok and my second question is...

my friend wants to make a spudgun. he will use pvc. he wants to use gun powder in it. i told him thats stupid. whos right and whos wrong, dr. phil?

Well, if he does do that he will die so....... he is right!

[gotbass7]

i saw one that was 26 inchs. but maybe i should do 40. if i can actually do this, itll be awesome

[paaiyan]

Let's put the gunpowder question down with this. The average chamber pressure of a .38 pistol is between 12,000 and 18,000 PSI. The PVC is rated to what, 125?

[gotbass7]

ya he told me hes not gonna make it now. hes still mad at killjoy though. lol.

[spudkilla]

Let's put the gunpowder question down with this. The average chamber pressure of a .38 pistol is between 12,000 and 18,000 PSI. The PVC is rated to what, 125?

PVC mixed with gunpowder is good for making frag grenades not spud guns....

[Killjoy]

oh and killjoy my friend says " WELL TELL HIM TO SHUT THE HELL UP, you tell your little spud buddy he needs to learn how to do some better stuff than shooting potatoes of pvc"

Ahahahahaha thats good, spud buddy hahaha... i can't stop laughing. Clearly your friend fails to realize i have expertise in many other fields, including explosives, high voltage, and BLACK POWDER cannons, but of course he is in intitaled to his opinion, and i would be mad too if someone implied i was possibly genetically inferier, which i apologize for.

And you should be able to get brushless pancake fans that are a little over half an inch in diameter at all electonics i think. I don't think they make fans that one inch exactly though.

[gotbass7]

i just need around an inch. the funny thing about the joke is i had to explain what you meant

[frankrede]

gun powder will blow up. it builds up thousands of psi. A small rifle cartridge builts up over 3000, a spud gun would be even more. it would build more pressure than the most advanced and efficiant hybrid around, dont do it.

as for the chamber fan, dont do it either. you obviously are not familiar with electric motors. those cheap fans are brushed motors. they create sparks that can set off the cannon before you even click the ignitor.

the fan MUST be brushless, period.

(note the period)

Wrong. There was a test with brushless motrs, even with a good fuel mix they could not get it to ignite using a non-brushless motor

[PCGUY]

So how did you plan on getting this to seal and fire over and over again?

Building a semi auto spud cannon is no easy task, especially with a combustion type. Your best bet would be to have something that could do say 3-5 shots using small "pre loaded" chambers that are switchable, but even that can become expensive and inefficient very quickly.

[paaiyan]

Well to reload ammo, you could have chambers rotate, like a revolver, and at a certain point, line up with a spring-loaded mag that would insert, say, a golfball. The front of the chambers could be open to allow for this, and a ball detent could be used to keep them from coming out. Then of course youd have to come up with a way to refuel them, and a way to seal them when they lined up with the barrel. As for ignition, you could have a spark gap in each chamber with two contacts on the outside. Once the chamber lined up with the barrel, two contacts on the frame of the gun could come into contact with those on the outside of the chamber allowing for the spark inside. refueling and sealing is the only thing I haven't got a solution for at the moment.

[Insomniac]

the funny thing about the joke is i had to explain what you meant

Thats the funniest thing I've heard all day, I would sig it but then I have to quote lots of other people to explain it. Oh well.

As for the combustion paintball gun, why don't you take a look at the timpmann c-3 (I think thats the one). Its a pump action combustion paintball gun.

[gotbass7]

well i thought i might load it with a paintball hopper. and i have a paintball barrel too that i just had from before.

oh and also i told my OTHER friend about my friend wanting to do the spudgun with gunpowder and my OTHER friend said that it would work with the tiniest ammount. im not sure. would it, or wouldnt it?

[pyrogeek]

Couldn't you just use a larger diameter chamber? And what about if you injected oxygen and propane? If you could regulate it correctly, then you could just inject just enough to work as if it was naturally aspirated.

[paaiyan]

Well it's pretty much universally accepted that pure oxygen with any decent fuel is a bad idea for a PVC gun. and I wouldn't trust even the tiniest amount of gunpowder in my cannon. How would you ignite it anyway?

[gotbass7]

pyrogeek are you talking about the gun? the reason i wouldnt do that stuff is it would complicated/expensive/and bulky. im not planning on this gun to be very powerful, just fun