new piston idea

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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spudthug
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ok well i dont know if this can be done or not but il explain it...

could u have a piston with the same size barrel as tee? like 1 inch tee with 1 inch barrel without going from 3/4 to 1"?

it would be like this..ur piston material (lets say teflon, thats wat i use) put orings on it and a stopper (screw?) so when u fill it it goes all the way into the barrel until the stop (stop cant be more than an inch in) it would hit the stop and the orings would prevent it from leaking..fill the chamber and when ready and filled, pull the pilot and the piston would be sucked back from the stop and air goes out the barrel...


i cant explain things good but would this work?
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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hi
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no, there will be nothing to push the piston back. the reason that there is because when you accuat the pilot, then that gap between the 1'' pipe and the 3/4'' pipe will take that small amout of air ond shove the piston back.

ps- 3/4'' pvc pipe doesnt fit into 1'' pvc pipe, so it would be impossible to do in the first place, unless you are using copper.
"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"
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boilingleadbath
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Short answer: no.

However, a 1" piston in a 1" tee with 1" porting is possible - it just has to be a chamber sealing valve.
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Velocity
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Yes, you can have a barrel sealing piston valve in a 1" tee with a 1" barrel... you would just need to have a 3/4" barrel port, and then use a bushing to increase that to 1" for the 1" barrel.

Yeah thats what i've done to hopefully increase performance on my latest gun, it has a 1.5" GB barrel and a 2" tee, so inside the tee i decreased the 1.5" barrel down to 1 1/4" bushing which the piston seals against.
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CS
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Just modeled up two possible configurations for both a chamber, and barrel sealing design in a 1" tee, with 1" ports. While I see no reason for these designs not working, you may want to wait for some follow up criticism. Also there may be a issue in there complexity for users with out lathes.

<img src="http://www.spudfiles.com/uploader/uploadFiles/019.PNG">
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