i've recently made a large piston cannon.

6" chamber 70" long
3.2" barrell 130" long (60" of that is inside of the chamber)

it has some HUGE recoil

shoots wine bottles full of water over 300meters (900ft)

shoots "rockets" over 450meters (1300ft)
these rockets are a piece of 1" PVC 30" long
atop ...

thanks for the help guys, went to the locla clark rubber store

got some sheet neoprene 1.5 and 3mm thick


seams to be working great,

k thanks for that, i'll try the neoprene

no home depot in oz.

we got stores like bunnings, mitre 10, which are just general building suplies stores

i was just wondering what type of rubber to seal the barrell everyone uses for their piston, what thickness too...

thanks for the help

hey guys, working atm on a second punamic. wanting to fire coke cans and bottles of 600ml capacity. meraning the barrell would be 65mm dia. would you think that a piston or a modde sprtinkler valve be recomended for this use. the connon would be in a "mortor" set up.

just wondering if anyone could shed some light on a topic i been wondering about

would a sprinkler valve or piston valve give more power?

if the same PSI and barrell and chamber volumes were the same

cheers

i use the same sort of ammo i use for my blowgun, except its heaver and stronger.

i use a think metal coat hanger,
cut the straight sections out
make a cone out of strong plastic of some kind,
glue / fix the cone onto the reat of the wire / rod
put the newly made dart in the barrel and cut the ...

how do u figure that u will have that much kick?

like u useing a formula or something?

its a Irritrol 204/205 Series - Richdel Valve

says its opperating pressure goes to 150PSI
it says the screw is a manual beeld



would useing this bleed to trigger the cannon damage the valve?

ok well it may soud strange to some of you but i recently bought a valve for a cannon i have now made.
i set up the elctronics for it(didnt want to 'soup' it up just yet), fired it a few times. great cannon, works perfect

i then notices a small black screw just to one side of the sloinoid, i ...

i made a copper ccannon, and am using a sprinklerr valve. where the copper piping go's into the valve i have an adpter from the local plumbling shop that is threaded.

the layout is somthing like this

copper barrel -> at the end of the copper a threded joiner -> a PVC threaded joiner -> valve ...