Twitches Science Project V.2. "SNCA"
- TwitchTheAussie
- Corporal 5
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Well ever since V.1 "Whompah Stompah" blew up from an attack of MAPP gas, I decided to rebuild it. V.2 is finished. I gave it the name "Spray and Click Affair" because thats basically what it is Anyway its just a basic cannon, piezo lighter and a fan. I screwed everything together so it wont separate after every shot, and epoxied it all up.
Had to give a demo today so that went good. Got 150+m with a cut up rubber ball and it gave me good marks just because it outshot the ballista a kid entered.
My problem is this. Being an avid shooter I know what a sonic boom sounds like and my cannon made one. Normally at most combustions make 30-40 psi and my c:b ration is a bit off bout 3:1 and despite the ball being wedged in tight barely halfway down the barrel but it still made a sonic boom.
How is this possible?
Had to give a demo today so that went good. Got 150+m with a cut up rubber ball and it gave me good marks just because it outshot the ballista a kid entered.
My problem is this. Being an avid shooter I know what a sonic boom sounds like and my cannon made one. Normally at most combustions make 30-40 psi and my c:b ration is a bit off bout 3:1 and despite the ball being wedged in tight barely halfway down the barrel but it still made a sonic boom.
How is this possible?
Raise your horns if you love metal.
CpTn_lAw
-spudgunning is like sex, once you've tasted, you can't wait til next time.
CpTn_lAw
my guess is that the gas expanding is the sonic boom and not the rubber ball it self.
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote
you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
- TwitchTheAussie
- Corporal 5
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Thats what I thought thanks man
Raise your horns if you love metal.
CpTn_lAw
-spudgunning is like sex, once you've tasted, you can't wait til next time.
CpTn_lAw
- spud yeti
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youre really lucky to have the excuse to build a cannon as a school project! As hi said, its probably just the gas, not the projectile(unfortunately!). Good luck for it, and I hope you get good marks 8)
really good quote/phrase here
- frankrede
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How sure are you that you broke the sound barrier?
Chronograph?
I doubt that a run of the mill cannon with a bad C/B and a poorly fitted ammo would break the sound barrier.
Chronograph?
I doubt that a run of the mill cannon with a bad C/B and a poorly fitted ammo would break the sound barrier.
Current project: Afghanistan deployment
- TwitchTheAussie
- Corporal 5
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The ammo fitted pretty tightly and Ive grown up around guns so I do know what sound something makes when it breaks the sound barrier Frank. And the cops let me off lightly just because I had an official note from the school saying I could make one.
Raise your horns if you love metal.
CpTn_lAw
-spudgunning is like sex, once you've tasted, you can't wait til next time.
CpTn_lAw
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Not a chance that you broke the sound barrier.
You can not tell how fast a round is going by just the sound. A very experienced shooter might be able to tell after firing many rounds of a particular caliber and varying loads and chrono'ing every shot. But, that knowledge would be completely useless when it came to a round as different as a "rubber ball". He would have to go through the entire process with the new round; multiple shots, varrying loads and a chrony, to learn what supersonic sounds like for the new round.
A spud gun does not have to be supersonic to make a hell of a lot of noise. A large CB ratio will make the gun much louder than it would be with a more reasonable CB. The sound you heard was nothing more than the "bang" of the gun itself.
You can not tell how fast a round is going by just the sound. A very experienced shooter might be able to tell after firing many rounds of a particular caliber and varying loads and chrono'ing every shot. But, that knowledge would be completely useless when it came to a round as different as a "rubber ball". He would have to go through the entire process with the new round; multiple shots, varrying loads and a chrony, to learn what supersonic sounds like for the new round.
A spud gun does not have to be supersonic to make a hell of a lot of noise. A large CB ratio will make the gun much louder than it would be with a more reasonable CB. The sound you heard was nothing more than the "bang" of the gun itself.
- TwitchTheAussie
- Corporal 5
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I never said it was the ball. I was just confused about how gases at 30-40 psi could break the sound barrier. Once again I will say in bold I know it wasnt the rubber ball I was just confused about how gases at 30-40 psi could break the sound barrier. I know Im not making much sense but I have personal reasons for it.
I just didnt think 30-40 psi would break the sound barrier by itself.
I just didnt think 30-40 psi would break the sound barrier by itself.
Raise your horns if you love metal.
CpTn_lAw
-spudgunning is like sex, once you've tasted, you can't wait til next time.
CpTn_lAw
- Modderxtrordanare
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You didn't break the sound barrier.
Spudding since '05. Proud waster of plumbing and plumbing accessories.
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- jackssmirkingrevenge
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30-40 psi is 15-25 psi more than the atmosphere, with that sort of impetus given the right conditions there's no reason why gasses shouldn't accelerate past the speed of sound.
hectmarr wrote:You have to make many weapons, because this field is long and short life
- jackssmirkingrevenge
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DDT? Isn't that a pesticide
Gasses reaching the speed of sound will make a sonic crack, that's why explosions are so friggin loud
Gasses reaching the speed of sound will make a sonic crack, that's why explosions are so friggin loud
hectmarr wrote:You have to make many weapons, because this field is long and short life