thank you guys for all the information. And thank you Gun freak for mentioning a chronograph, as it will solve some problems. because now I can shoot though a chronograph in to a back stop rather than just shooting it and measuring the distance. the chronograph will eliminate some variables.

For my science project I am going to build a air cannon and fire it at the same pressure and angel but with different density gases ,and see if the projectile would go different distances. My original plan was to use helium, air, CO2 and Sulfur hexafluoride. I need help with two things, first, do ...

Can you solder metal other than copper? If so what metals can you solder, and is the connection as strong as with copper?

Edited by jrrdw.

What tipe of threads does a paintball tank have? I want to have one as the air supply on a bbmg. I'm planing to make.

I know I touk out the interior of the valve but I still cant get to the spring

could you like tell me exactly how cus i have know clue how to

any way to do it without a special tool?

ohh ok sory one more question how do you get the sprinh out I tryed to figer it out but I coulden't so I thout i'd ask rather than brake it

by cracking pressure do you meen the pressure at witch it fails, and why would taking the spring out help?

I was wondering if a shrader could be used as a check valve for use in a piston valve or any thing else?

Thanks jeepkahn people kept talking about qev guns and din't know a qev was.

what is the differences between a qev and a piston valve? Sory if this is a stupid question
ps what's a easy test qev?

Sory I'v never scaned something on to a computer before.

How do you draw and scan something?

What do you use to draw pictures of cannons on posts?


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