SpudFiles

ok im new to the site so bear with me!!! ive built some paintball projects in the past and have just started building a tank, ive built a antitank cannon previously and it worked fine.........when someone watched my video on you tube told me i was lucky to be alive ie unsafe equipment. see link below to watch video. anyways i need to build a new cannon both for the new tank and also for the anti tank gun......here are some of the requirements. according to paintball field standards no homemade devices may exceed 250 psi. id like to have both setups breech load like my anti tank cannon.....see video......all devices must also have a safety blow valve set at that pressure. i would also like to use a electronic firing if possible ie sprinkler valve. anyone with any info, designs, or schematics would be greatly appreciated!!!!! check out my videos and let me know!!! im need your expert advise thats why im here!!!

Unsafe equipment? Perhaps some pictures would be better for judging that.

Pictures would also be good to see how far along you are with your cannon-making skills.

As to your designs, just take a look around in the showcase sections. There's more information than you would care to peruse there. Also, check the wiki.

Specific questions are good. If you go with an electronic sprinkler valve, it's as simple as wiring a switch in series with the solenoid and a 24VDC supply... really nothing to it.

basically im using two ball valves one to fill one to fire and a 16 inch 1 inch steel charge chamber and filling it with co2 which i guess is dangerous? [/img]

if it whas metal and it was properly scred ...no cross treadds

i think it may be fine

If the pressure is limited to only 250 psi and you want to maintain the convenience of CO2, there are two options that I can think of.

Option 1: Use a regulator. Since you are familiar with paintball, you should be familiar with these. Palmer's Stabilizers are cheap and easy enough to get and can be configured for just about any purpose. If this option is chosen, though, you might want to think about using a bigger chamber. Assuming you plan on firing the Nerf Vortex, you can expect them not to have much range coming from a 250psi, 16" x 1" chamber.

Option 2: This option is what I call "chamber manipulation". This occurs when one chamber is allowed to fill to the maximum pressure of the CO2 (which is dependent on the tank's temperature and usually runs anywhere from 800 to 1200 psi) then shut off from the gas. This chamber is then dumped into a larger one to bring down the pressure of the chamber. It works off of the P1V1=P2V2 equation and is pretty effective without the need for a regulator. If this option is chosen, several members here can assist with any questions that may arise.

As far as valves are concerned, there are a few choices. If you're set on a sprinkler valve, you're gonna have to cut pressure (which means you'll need a larger chamber to compensate). There are high pressure sprinkler valves available, but the companies like those things (i.e. expect to put out some cheddar for 'em). Oh, and be sure to check out The Sprinkler Valve PDF found in the Hubb Library or in the Pneumatics Section of this site.

Alternatively, a QEV would work well. They tend to have a pressure rating higher than sprinkler valves, are easy to incorporate into a launcher, and have a decent price. You may have difficulty finding them locally, and you will have to sacrifice the use of electronic fire control, but they are a viable option.

Of course, you could build a valve, and this will allow customization of however you want. Any number of valves can be built, just as long as the parts can handle the pressure.

Okay, I'm gonna stop now. This post is long enough.

you can still pilot a qev with a 1/8-1/4 inch sloinod valve to keep your electronic fire.