The burst disk idea is good its just the problem of the gun firing when you dont really know. I might consider it, but right now I just want to make things as simple and cheap as possible and get it built, so im using a ball valve for now. But I might choose to do a few upgrades further on in time :...

BlackH... here a link to his thread http://www.spudfiles.com/forums/bh-2400 ... 14078.html.

Hes quite a skilled builder

Haha thanks! I can confirm i have seen another South African here, so im the second!

But it will be very hard for me to find one as I am in South Africa, so I think I will have to stick to ball valve as its available. A ball valve will take the pressure but I undestand that it will decrease the performance due to the slow release.

But we are unable to get the parts to make a piston valve.

What kind of valve could I use that will take such pressures?

Yes we are using 5mm thick galvanized steel tanks, a safety blowout valve, and a regulator to keep track of the pressure build up.

Hi all my friend am I are about to proceed in building a pneumatic cannon that will use dry ice to have a constant source of pressure. We will be using a galvanized steel tank and will hopefully be able to run it at about 10 bars. The firing mechanism will be a ball valve, what are your thoughts on ...

Hi spudders Don't you think that a cannon hall of fame of some sort on this website would be great? I think it would be nice if the select few of truly outstanding, honourable and innovative cannons can go into it and be viewed by all the users. And of course if you win the competition on spud files...

Thanks for all the useful info guys!

Yes I realised that already, thats why I was asking if I should have a smaller or larger chamber to barrel ratio in my cannon to get the most "ooooomph" out of it.:roll: I hope to start building it soon, it is going to be based on a MG42 machine gun with a unique magazine bolt action loading system!...

Ok thanks, I was planning on using SCH 80 piping, or should i rather get SCH 120? For the barrel I plan on using copper pipe so it does not sag or bend.

I downloaded the HGDT and it doesn't work. I get an error reading "Runtime error 339 Component MSCHRT20.OCX or one of its dependancies not correctly registered: a file is missing or invalid."

I downloaded it twice and it still doesnt work.

Hi fellow spudders I'm new to SpudFiles here, and I have a question. (I did search) My friend and I are planning to build a combustion cannon, and I am yet to work out the PVC dimensions according to an ideal C:B ratio. I have looked on the spud files wiki, and I read that "a C:B ratio of about 0.6-...