hmm ok so basically you wont have enough time to do more than two shots at good fps. thanks for the help

Well I was wondering about the sprinkler valves. I know how to make em work but I don't understand them very well.

So I would like to know, if you squeeze the handle to make the valve open up, can you let go and it will close again? Or does it open up until all the air is gone?

Basically I'm ...

Also, all of those explosions in the video are not from the artillery shell. The huge ones are from test bombs but not the artillery shell. Just incase u didn't know

ok thanks, good to know

Would this setup decrease fps? I was thinking of having a 4" resevior then reducing it to a 1 inch with sprinkler valve and then going to 2" for the barrel. THis would be cheaper than getting a 2" valve.

Thanks for the help guys, just wanted to make sure I got everything right BEFORE I put it together =)

So if I went with this 4" to 2" socket-weld reducer bushing
And then went to a 2" to 1" socket-weld reducer bushing, I would be able to be safe at 100 psi?

Ya but they don't seem to have 4" to 1" reducer bushings. Anyone have any suggestions?

Would it matter if I went from 4" to 2" then from 2" to 1 "?
And for it to be pressure rated I want it to say NSF?

The one's at mcmaster say ASTM and NSF.

But then they say never use plastic pipe fittings for ...

Well my last cannon I built someone told me that the reducer I had used was not pressure rated so I couldn't push it past 60 psi.

I'm planning on building a standard pneumatic that will be safe to 90-100 psi.

I'm planning on using 2 feet of 4" SCH40 for tank and then reduce to a 1" barrel with an ...

I'm not trying to be a leach I just came here hoping for someone to answer my questions seeing as this is the spud cannon questions part of the forum.

ok thanks leadbath, very helpful

Ok, a two foot long 2" tank with an endcap and 2"->1.5" reducer bushing then a rainbird 1.5" sprinkler valve (can someone help me find where to get it?) and then 3 feet of 1.5" pipe. This should all be pressure rated so I can launch at 100 psi right? One last thing I need to know is, where should I ...

Ok how about a 4 foot long 1.5" barrel with a 2 foot long 2" tank. Can you recommend a sprinkler valve and explain how I would use it?

Also what is the difference between SCH40 and SCH80?

Well I'm going to build my next pneumatic cannon and I need to know some good pressure rated pieces. I want to have a safe launch of around 100 psi. Now, I am planning on using 2 feet long of 4 inch SCH40 piping. And 4 feet long of 1.5" sch40 piping. The pressure max for 4 inch is 220 and for 1.5 ...

You're using too much axe (or pam, or hairspray). Any fuel needs oxygen to burn. Except oxygen, of course :D

Oxygen is an oxidizer I thought, so it would need a fuel to burn. Maybe I'm wrong though.

Pure oxygen is highly flammible, the reason why you can light a match is because of oxygen but ...