Page 48 of 101

Posted: Wed Nov 28, 2012 11:18 pm
by dewey-1

Posted: Thu Nov 29, 2012 6:55 am
by PaperNinja
Looks like adapters aren't too hard to find on ebay: http://www.ebay.com/sch/i.html?_odkw=sp ... T&_sacat=0

Posted: Sun Dec 02, 2012 3:47 pm
by PaperNinja
How much pressure d'ya suppose the in stock barrels here can take?

Or the .177 in stock barrel?

Posted: Sun Dec 02, 2012 3:49 pm
by jackssmirkingrevenge
I reckon you could use them for a 22LR rimfire, at least 10,000 psi.

Posted: Sun Dec 02, 2012 3:56 pm
by PaperNinja
Even the .22?

Larger ID + same OD = thinner walls = less pressure, I'm thinking.

Posted: Sun Dec 02, 2012 3:58 pm
by jakethebeast
But as you see, the bigger calibre barrels are thicker. Normally .308 barrels are not very thick, and the pressure is pretty much more than your average spudgun :wink:

Posted: Sun Dec 02, 2012 4:00 pm
by PaperNinja
The thickest barrel for both .177 and .22 has .630 OD

Posted: Mon Dec 03, 2012 1:35 am
by jackssmirkingrevenge
Even the smallest OD 0.22" barrel offered on that page will be suitable for at least rimfire firearm pressures.

Posted: Thu Dec 06, 2012 9:53 pm
by PaperNinja
Ok so last question...

These say they're rated for 6500 psi, but the description also says: "Note: Pressure ratings given are for static (constant) pressure conditions."

Should these be ok for pressure spikes at a max of 5000---or possibly more (<6000)---psi?


Edit, oops, it doesn't link to the specific type. Anyway, they're shutoff valve quick disconnects rated to 6500 psi (static).

Posted: Tue Dec 11, 2012 3:12 pm
by DigitalSpuds
For the discussion about best barrel types and distance, I found this article comparing barrel length, type of valve, etc. to get the best combination.

http://www.sigmazone.com/Taguchi_L12_SpudGun.htm

Posted: Wed Dec 19, 2012 10:52 pm
by MrCrowley
Okay, so I picked up one of these because my stungun stopped working and even though it's >30kV, I'm worried that it is only able to jump a 10mm gap. Does anyone think this may be a problem for 10x hybrids? I know piezo sparkers have no trouble but all the ones I've tested can jump closer to 20mm.

Apart from that, it's a nice piece of equipment. I'm fairly pleased with it even though it was $30; it sparks much nicer than those BBQ push-button sparkers that also operate on AA batteries.

Because I'm using it in conjunction with my new 12V LED controller for remote ignition I have to use one 9V battery wired in series with three AAA batteries to get the 12V controller to operate, then I have to step-down the output to 5V using a 12V USB car charger and then I have to step-down the output of that using three 1N4004 diodes in series to get ~3V @ 700mA for this electric sparker :lol:

edit: the unit is smaller than it looks and is quite tidy with good insulation. Unlike with the stun gun circuit I was using, I don't think this one will short-circuit.

Posted: Fri Dec 21, 2012 11:19 am
by PaperNinja
Is discussion of solid propellants legal in a PM?

Posted: Sat Dec 22, 2012 4:26 am
by jackssmirkingrevenge
They're private messages by definition, make of that what you will ;)

Posted: Sun Dec 23, 2012 1:02 am
by Lockednloaded
More of a curiosity question:

If I were to flip a QEV diaphragm around and drill a hole through the middle, would it work as a chamber sealing valve?

Posted: Sun Dec 23, 2012 7:22 am
by pneumaticcannons
Heh, actually a pretty cool idea. In theory, I don't see why it would't work, however, in practice, the "skirt" around the qev might give away.