SpudFiles

Hi all,

i am new to this forum but i must say i read a lot of interesting ideas. I am designing a helium powered cannon for small particles. These particles are so called fsp's and rcc's

right circular cylinders (RCC) and fragment-simulating projectiles (FSP) are used. RCCs and FSPs are non-deformable (hard steel) projectiles normally ranging in weight from 2 grains to 64 grains. They simulate fragment impacts from hand grenades and land mines.

Now have i got the basics working. It can shoot etc, but it needs a redesign since it is not practical. The first tests where to see if we could reach the needed speeds accurately enough. And it does do speeds of 600m/s using helium and the right barrel. Sorry i am in a metric country And for that we need pressures up to 200bar. I wanted to upgrade the design with a qev valve and though i can find quite some information on them and can't seem to find if there are stock ones that can handle 200bar.

So i was wondering if there is anybody overhere that knows any.

Regards,

Per

I don't know, are you stuck with something like this

Welcome to spudiles!

For your requirements, I think a burst disk is a much better idea for a valve and indeed most high speed gas guns employ such technology.

are you stuck with something like this

Tiny orifice but it could be a decent pilot for a small QEV. I have used a schrader to pilot a 1" diameter piston valve in the past.

Well we are using a setup with kind of a burst disc at this moment, but that isn't the way to go ahead. I want to automate it more (i am a software and electronics developer during the daytime). I already use valves that are rated more then enough, but they aren't fast enough to release all the gas .
And now i am looking at a good valve design which will suit the project. Doesn't have to be a qev, could also be a piston valve (or any other type). And since there is so much knowledge overhere i started searching through the forum. Maybe the best option is to have somebody machine one for me (i can't do that myself), but then i would first need to figure out how to calculate / design something . Because i can't seem to find qev's with these kind of pressure ratings. If there are any people that could help with this (payed is nog problem) then please do respond!

So currently i have got a remote controlled regulator to control the pressure, because we don't just want to shoot as fast as possible. We won't to shoot at a certain speed. The setup is pretty basic, we pressurise a chamber and we release the gas by mechanically pushing the projectile a little forward into the barrel. We can shoot at speeds of around 600 m/s without any problems, single shots work just fine. But i need to do around 7 to 15 shots and it is to much work at this moment after each shot.

per-i wrote:We can shoot at speeds of around 600 m/s without any problems, single shots work just fine. But i need to do around 7 to 15 shots and it is to much work at this moment after each shot.

I see why you need something easier to set up. What is the caliber of your barrel?

Doesn't have to be a qev, could also be a piston valve

Basically the same thing, not the most complex thing to engineer.

I could probably help. I have a vey nice stainless steel 1/2 " T fitting with very thick walls well suited for high pressures. I could machine suitable parts for it from stainless steel to make a piston valve from it. I'm a professional cad designer and cnc machiner. (I'm from Finland, so metric units and bsp/G threads)

I see why you need something easier to set up. What is the caliber of your barrel?

Currently i am testing with 1.1 gram fps, so the simulate a .22 caliber

Basically the same thing, not the most complex thing to engineer.

Well if you would ask me something about software or electronics development I would give the same answer most of the time. And i do own my own cnc machines for woodworking etc and i do quite some designing and fabrication using 3d printers. This is just a bridge to far for me at this moment (at least i think) to just do it by myself. And i always say, when in doubt find somebody who knows more then yourself (and try to learn).

I could probably help. I have a vey nice stainless steel 1/2 " T fitting with very thick walls well suited for high pressures. I could machine suitable parts for it from stainless steel to make a piston valve from it. I'm a professional cad designer and cnc machiner. (I'm from Finland, so metric units and bsp/G threads)

Wow great. Always handy to have somebody that also uses metric. Not that imperial is an issue, but i can always convert things. But it sometimes is easier for me to learn, if i read tutorials etc then i get a faster idea in my head on wall thickness etc. But i guess people have the same issues if they aren't used to metric and need to convert everything back to imperial

How do we get in contact?

Not that any other help isn't appreciated of course! I am currently designing an auto loader for this setup also. Using a vibrating hopper and i am going to 3d print it first (just to see if the setup is going to work).

Currently i am testing with 1.1 gram fps, so the simulate a .22 caliber

Do you use sabots or does the fragment simulator fit directly into the barrel?

Well if you would ask me something about software or electronics development I would give the same answer most of the time.

Naturally, everyone thinks that their own specialized field is child's play

If you're at liberty to say, are you working with the development or testing of ballistic protection?

I am at liberty to say On of the thing i write software for (and create electronics) is indeed in the field of ballistic testing. But that is just one of the thing i develop for, i also design/build software/electronics for hvac systems etc,

But this is sort of a side project that somebody started in the past and it has taken my interrest (and now my spare time also). So i revived an old system and did some tests with it. The tests showed that parts of the design work (and some parts are totally wrong/unworkable). And if somebody says it can't be done, like with this old system, then that always triggers me to see if that is totally true.

ok don't know for how long my post need to be approved first, but i forgot one thing in my previous answer

They fit into the barrel directly

per-i wrote: Wow great. Always handy to have somebody that also uses metric. Not that imperial is an issue, but i can always convert things. But it sometimes is easier for me to learn, if i read tutorials etc then i get a faster idea in my head on wall thickness etc. But i guess people have the same issues if they aren't used to metric and need to convert everything back to imperial

How do we get in contact?

I will send pm (private message) to you, take a look.