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my idea is to make a bolt-action gun where I can get between 3-5 shots off without refilling I will be using a modified solenoid valve. it will be all copper design so it will be able to hold high pressures. I'm going to fill the air chamber through a ball valve from an air cannister which will fill the tank at 350psi which I will run through a air regulator to bring the pressure down to 70psi before it reaches the solenoid valve. I'm not sure if I should use a solenoid or if I should use a more efficient way like a piston.

Was there a question?

Welcome to Spudfiles.

yes the last sentence was meant to be a question. I' planing to have this done by new years day

Piston valves are kinda tricky to get working. For a design like yours I'd use a QEV or a modified sprinkler like the one shown on the home page.

I have a sprinkler valve at home I don't know where to get a QEV from and im not big on the idea of shipping one into AUstralia

To get more than one shot per loading do this:

Have a large, "main tank". This hold your air supply. Then have it connected to a much smaller tank through a ballvalve. Your modified sprinkler valve would be attached to the smaller tank. To refill the smaller tank for 1 shot, open the ballvalve to fill the small tank, and then close it when you're ready to fire.

Good luck and welcome to spudfiles.

i had that as an original idea but the power of the shot would reduce everytime I shot unless I have a large high pressure tank then a ball valve then an air regulator which fills a smaller tank at a pressure that the sprinkler valve can handle. my only problem with this is I dont want the extra trouble of opening the bolt loading and having to open the ball valve too.

If I'm understanding your OP, you intend to;

Have a "main" pressure reservoir @350psi. This reservoir feeds a regulator set to an output pressure of 70psi, used to charge the "firing" reservoir.

From there, the air travels through your valve (type to be determined) and down the barrel.

If you added a small valve (needle valve) between the regulator and the "firing" reservoir, you could control the fill rate.

The flow would have to be low enough to allow the (let's say) piston to pilot properly, and high enough to reseat the piston when the pilot valve has been closed.

Should also work with a qev.

Once the valve is set, it should be good to go.

Shouldn't be too hard to get working if you don't need an overly quick reload time.

What tools do you have access to?

my dad is a plumber and all his friends are tradies so pretty much anything

Gippeto wrote:If I'm understanding your OP... when the pilot valve has been closed.

your correct in your understanding. the problem is with a QEV is I don't know where to get one and i dont want to import

Aussie right?

i recently read a thread (i'm just full of rhymes tonight ) where someone mentioned http://www.bellpro.com.au/

Hope that helps!

they only have one king of QEV in the site click the link to see it I'm not sure if it is the right type though beacuse i havent seen any QEV like it on spudfiles

http://www.bellpro.net/xcart_program/pr ... 268&page=1[/url]

The problem with solenoid valves in "repeater" applications is that they tend to take a while to reseat after firing, or not reseat at all given a low airflow. I would either shop around for a QEV or if you still want to use the solenoid valve, incorporate some sort of spring that would help it seal again after the pilot valve is closed.

The QEV you linked to looks like it would be suitable for an airsoft-marble calibre launcher.

I think I'm saying pretty much what everyone else is saying, but you could have several tanks (maybe four) all connected to the solenoid. Just open up each tank with a bv and close it and open another for your next shot.

i think I will by the QEV from the website and I'm thinking about using a piece of 1/2 inch copper pipe as a barrel.
@SPOOK I would prefer to keep just two tanks like i wanted to earlier because I want to keep my gun compact and 4 tanks would take up too much room