High power coaxial Idea.

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thrasmussen
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Fri Apr 20, 2007 1:49 pm

I was thinking of making a coaxial cannon with a 2” barrel and a 4” main chamber with 2-4 auxiliary chambers connected to the main. The Barrel would be 5-10’ long, chambers would be 5’, and the cannon would fire using the diaphragm method. The pilot valve would be nothing more than a Cork type device with a pin to hold it in, hopefully by doing this I will get super fast firing and a projected range of about 200-250 yards.
It also will be set up as breach loading.
Any ideas that would benefit this project?
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spudthug
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Fri Apr 20, 2007 1:51 pm

u cant use a cork as the pilot it would never hold it would fly out and hit u...hard...but it may work but why coaxial if its going to be huge??
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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thrasmussen
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Fri Apr 20, 2007 1:59 pm

Well I wouldn't use a literal cork but something to that effect. I wanted to get away from the over-under method. And I can't easily make a Piston gun.
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boilingleadbath
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Fri Apr 20, 2007 2:19 pm

The performance benefit from such an oversized chamber is minimal (but feel free to model it with the GGDT to decide if it's worth it), and if performance is the ultimate goal, a [triggered] burstdisk system will serve your goal better than the proposed system.
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thrasmussen
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Fri Apr 20, 2007 2:28 pm

I was told that Pressure doesn't matter as much as valve speed and volume. Is this true? How would the burst disk design work on this cannon? And I would use GGDT but I don't fully understand it, I usually just theorize try it and see if it works. I know it's not the best method but I've developed a pretty good sense about a good design.
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lukemc
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Fri Apr 20, 2007 3:39 pm

thrasmussen wrote:Well I wouldn't use a literal cork but something to that effect. I wanted to get away from the over-under method. And I can't easily make a Piston gun.
pistons realy arent that hard but if you still dont think so i havent seen it done but im sure its posible to make a diaphragm (its gona be a big one though) inside T joint for an over under. i seems overly compex to make a coaxail that big
"Those who are different change the world. Those who are the same keep it that way"
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thrasmussen
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Sat Apr 21, 2007 7:21 am

I thought of it as simple. because the only moving parts are the diaphragm and the firing device. I only have to bore out a few fittings as well. But one thing I do know is that I will most likely need some kind of support for the diaphragm.
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spudthug
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Sat Apr 21, 2007 7:28 am

i heard that phrams are harder to make than pistons...just go get a big ass bag of hotglue and get a junk peice of pipe of whatever size ur using then spray it iwth pam and melt a crap load of hotglue into it....bolt some rubber on it and drill an equilization hole in it and ur good...
4" piston valved cannon-half done..( i spilt my cement...)

Hybrid- 75% done. need to build propane holder and drill/tap sparkplug hole..
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frankrede
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Sat Apr 21, 2007 10:56 am

If your having all these auxillary chambers why not just make it over under?
The performance would be better and you would have alot less things to worry about it.
Current project: Afghanistan deployment
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thrasmussen
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Sat Apr 21, 2007 11:11 am

I started with an over-under. I just don't want to use that design for this one. But things could always change.
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