SpudFiles

my first pneumatic, its more of a rifle than a cannon. cost me around AUS$60 to make. works well at 50psi, but i dont know what type of pvc im using, it doesnt have any printing on the pipes so I wonder how much pressure it could take. It uses a 12bar small, cheap sprinkler valve, air gun trigger, schrader valve, 25mm pvc for chamber and 15mm for barrell and a number of reducers and fittings. shoots batteries well.
http://www.instructables.com/id/pneumatic-sniper-rifle/

you should be safe around about 120PSI easy. Those fittings look exactly the same as mine, might just need to shorten the pilot hose a tad. but overal very nice for a first!

fittings arnt everything thursto, you have to remember the pipe aswell...

Well the fittings look the same as the pipe, so i never seen any other 3/4" pipe not pressure rated (excluing electrical and hat not because it wouldnt fit in the fittins)

i have seen 3/4" dwv in bunnings

serious? the smallest diameter ive seen there is like 2" well you learn something new everyday.

@stick where abouts do you live in australia?

not bad for a first effort, though you should tap the blowgun directly into the sprinkler valve, you'll get better performance and retain the ergonomics.

Uhh Thursto...the piping is covered in black -electrical- tape.

How would you know?

Back to Stick's gun. Next time when your making a pneumatic cannon, try not to have the chamber be the stock =/.

OuchProgramme wrote:Uhh Thursto...the piping is covered in black -electrical- tape.

How would you know?

Back to Stick's gun. Next time when your making a pneumatic cannon, try not to have the chamber be the stock =/.

What's wrong with having the chamber as a stock? It's a uniform shape with not too many air flow restricting bends. If he wants it like that, surely he has the right to make the guns how he wishes. All we can do is point out any dangerous floors that new spudder's might come across.

That's a top looking first gun mate. (Sounds like a friggen' hipocrit for what I just said...) but try and keep the pressure on the lowish side untill you find out what sorta pipe your using.

All the best.

OuchProgramme wrote:Uhh Thursto...the piping is covered in black -electrical- tape.

How would you know?

Back to Stick's gun. Next time when your making a pneumatic cannon, try not to have the chamber be the stock =/.

Usually down pipe has no writing on it, so I am very worried it's not pressure rated. For a plumber to install pressure rated pipe he needs to be sure it's pressure rated, that's why it's written on the pipe.

With down-pipe (spouting) it holds no pressure, and is on the outside of a house so it needs to be clean, so the writing isn't necessary.

Mmm it might just pay off to get pressure pipe and rebuild ya chamber matey, I know it's a bit of money down the drain but it's not worth getting yourself hurt or worse.

The only thing is, in my experience DWV fittings don't work with pressure rated fittings, but if i'm right, this isn't DWV, it's spouting, which is worse. I've never worked with spouting much so i'm not sure of it's compatability.

Mitchza89 wrote:What's wrong with having the chamber as a stock?

In theory, stresses. The chamber is being subjected to the effects of depressurisation as well as recoil forces. But in a launcher this size, recoil is not too bad.

It's not too major a concern, I'm sure we've all (or at least most of us have) done it at some point.

Currently I use my piloting QEV as a stock - works quite well, and reduces turning force from recoil because it's straight behind the barrel.

wow, I cant believe how many replies there are. anyway this is everything I know about the pipes I used.
-bought from bunnings, (sydney) [pvc-pressure pipe fitting 13558 25mm class 12 pipex $6.25] this is what the reciept says. maybe someone knows what pipe it is and the max pressure rating.

if thats what it said on the pipe its definately pressure rated hence the pressure pipe lol you should be fine up to 120psi or so ive nevre gon higher than 110 or so and thats very powerful. btw nice first gun very clean