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Posted: Tue Feb 19, 2008 6:41 pm
by SpudFarm
it is just to screw the piston in there to the pressure you want then close the valve between the chamber and pump (not on picture) and let her rip

Posted: Tue Feb 19, 2008 6:45 pm
by Sticky_Tape
I meant my drawing and the calculations for it.

Posted: Tue Feb 19, 2008 6:46 pm
by SpudFarm
okey it sounded a little strange :?

Posted: Tue Feb 19, 2008 6:49 pm
by Sticky_Tape
What would you use for the barrel?

Posted: Tue Feb 19, 2008 6:50 pm
by SpudFarm
just the same as on my marble gun. 1/2" copper pipe at 6 feet

Posted: Tue Feb 19, 2008 6:54 pm
by Sticky_Tape
I don't know for sure but would the o rings on the piston seal the pump pipe?

Posted: Tue Feb 19, 2008 6:55 pm
by SpudFarm
it is really hard to seal 100% with homemade stuff. but if you cast a long piston and put 5 or more o-rings and a sealing face on it will work ;)

Posted: Tue Feb 19, 2008 6:59 pm
by Sticky_Tape
I would go for a .177 caliber bb gun barrel. And make the gun useing my idea but make a pistol the pump pipe would be .75 inch pipe.

Posted: Tue Feb 19, 2008 7:03 pm
by SpudFarm
if i house the piston is an empty co2 cartrige i can get a good pressure for a really small kalibre;)
acctualy the only thing needed is to cut the bottom of a cartrige and put a piston device in it then put the whole thing in an Co2 gun then shoot. should work

Posted: Tue Feb 19, 2008 7:16 pm
by Sticky_Tape
I would rather just use the materials I have instead of buying a co2 gun

Posted: Tue Feb 19, 2008 7:17 pm
by SpudFarm
i have a co2 gun :- )

Posted: Tue Feb 19, 2008 7:27 pm
by Sticky_Tape
maybe a rifle would be worth my while

Posted: Wed Feb 20, 2008 12:26 am
by ammosmoke
Ok, I think this may help you... The word "of" is not "off". Off, means not on, or not correct. Of, is the essence. "I have too much 'of' this." Not, "I have too much 'off' this." And vice-versa. Sorry its just driving me crazy. You guys have horrible grammar and spelling. I am not a moderator, but trust me it doesn't earn points with them.

Posted: Wed Feb 20, 2008 3:37 am
by lockmanslammin
Just a thought here, you say you want to compress it to 150 and then pump it with the piston to double that?...
You know that if the surface area of your piston is one square inch that you would have to push 300 pounds of force on the handle right?
PSI=pounds per square inch
so if you are using a pipe that has an internal diameter of .75 inches than it would take about 132 or 133 pounds of force on the pump to achieve 300 psi.

just a thought... Lock

Posted: Wed Feb 20, 2008 5:08 am
by psycix
spudchucker wrote:I just did this up on paint and do you think this would work?
Pressurize, pump and lock the catch mechanism.
Then unlock the catch to use it as a pneumatic hammer! :D