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Posted: Wed Jun 27, 2007 4:02 am
by Redcoat
oh right.

Would it penetrate paper at 10 metres?

i mean i just want to make it like that so i can go woop i have a gas ram gun.I can also use a direct feed to barrel if i want.

Posted: Wed Jun 27, 2007 5:04 am
by jackssmirkingrevenge
If you use say a 15 inch airsoft barrel, then a BB would definitely go through paper at 10 metres.

Posted: Wed Jun 27, 2007 5:04 am
by Redcoat
by 15 inch do you mean calibre? :P

Posted: Wed Jun 27, 2007 5:15 am
by jackssmirkingrevenge
Imperialist1 wrote:by 15 inch do you mean calibre? :P
yes, that´s exactly what I meant:

Image

:roll:

but seriously, if you use attach your chamber and ball valve to say a 6 inch long piece of 1 inch diameter pipe, in which sits a piston, and then attach it to say a 12 inch long section of 0.25 inch inner diameter ( :P ) section of barrel, you should get more than adequate performance, probably much better than a typical airsoft pistol if you have a big enough chamber with sufficient pressure.

Posted: Wed Jun 27, 2007 6:00 am
by Hotwired
jackssmirkingrevenge wrote:
Imperialist1 wrote:would it be possible to make one of these using a pneumatic setup i.e. have a chamber and then say a ball valve and then the piston inside a cylinder on that?
Talk to Hotwired, I think he had made a prototype along these lines.

The way you drew it, you can only get as much pressure developed by the moving piston as there is behind it, so it wouldn't give better performance. What you want is a bigger piston propelling the compression piston
I don't remember posting it in Spudfiles but yes I had a go at a gas ram thingy.

Pneumatic Ram Barrel

It was a bit inconclusive as to whether it improved performance or not, I had a go at putting minature burst disks in there to increase the pressure spike hitting the projectile but I didn't take it very far.

Posted: Wed Jun 27, 2007 6:23 am
by jackssmirkingrevenge
Hotwired wrote:I don't remember posting it in Spudfiles but yes I had a go at a gas ram thingy.
No I had seen it on UKSGC.

It suffered from the same pitfall as Imperialist's design above - since the air is acting directly on the same piston that's doing the compressing, then it cannot develop more pressure than itself. Fine, so there's the momentum of the piston to be taken into account, but the benefits are going to be minimal. What you need is a larger diameter piston pushing the compressing piston as in my diagram above if you actually want to enhance performance.

Posted: Wed Jun 27, 2007 4:08 pm
by Redcoat
jackssmirkingrevenge wrote:
Imperialist1 wrote:by 15 inch do you mean calibre? :P
yes, that´s exactly what I meant:

Image

:roll:
note my :P smiley at the end. :D

Anyway today i will make my first original idea and then later on ie tomorrow i will go ahead and build your idea jack. :)

Posted: Fri Jun 29, 2007 11:54 am
by jaffe
For this that system you could better youse a Nerf valve :idea: .
Greetings from the dutch, Jaffe

Posted: Fri Jun 29, 2007 8:20 pm
by Redcoat
ok im starting construction in an hour or so problem being.I have a blowgun instead of ball valve stupid hardware store didnt have a ball.Will it still work?

Posted: Sun Jul 01, 2007 12:50 pm
by jaffe
Ofcourse it will qork with a blowgun valve, it wil even work much better.
Greetings from the Dutch, Jaffe

Posted: Mon Jul 02, 2007 2:43 am
by jackssmirkingrevenge
A blowgun should provide enough flow for your purposes, sounds like an interesting little project :)

One piece of advice, make sure your piston in airtight and your projectile is tight in the breech to allow enough pressure to build up behind it before it starts moving - consider how a springer rifle works :wink:

Posted: Mon Jul 02, 2007 2:57 am
by Redcoat
alright. :D . the message was too short.i dont like salty water im freshwater