what type of cannon should i build next??????

[ajb12345]

Hey im new to the forums and have only made one cannon(over under sprinkler valve. i will post it but its not anything special) Now i want to make another one. I am going to make it a piston but was wondering if i should do another over/under or if i should go coaxial. Its going to have a 4 inch diameter chamber and 2 inch barrel. also how hard would it be to pump this with a bicycle pump. thnx for the info.

[OuchProgramme]

Woah..if its gonna be that big of a bore i suggest a combustion

[ajb12345]

my dad wont let me. only pnuematic. so i decided why not go big. oh and if someone could post a link on how to make a good piston it would be helpful or i will just do some more searchin myself

[Maniac]

Why will he not let you make a combustion cannon.

[frankrede]

With dimensions that size I recommend a coaxial

[DYI]

Why can't you build a combustion launcher? For a first build, you'll be far safer with one of those than a pneumatic (no constant pressure, generally less pressure produced), and you won't have to worry about an expensive 2" valve.

If you're really intent on pneumatic, as frankrede stated, a coaxial pneumatic piston valve is probably the way to go?

[ajb12345]

thnx guys. yah thats what i figured but wanted to make sure. the hardest part is going to be getting the money and making the piston

[DYI]

the hardest part is going to be getting the money and making the piston

Actually, if you're creative enough, you could probably do this for under $100, if the parts are available locally. What material do you plan on using?

[MrCrowley]

This is for a 2" piston but it gives you the general idea of how to make one:
http://www.instructables.com/id/Golfbal ... -Build-one -That-Shoo/

[n-strike]

I suggest a coaxial even if I was also planning on building a 4" chamber overunder.