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Posted: Sun Mar 29, 2009 2:58 am
by Brian the brain
I'm interested. Got more than a picture?
Not really.I've only got the story to go with it.

I have had several 12 grams in there.And I'm still here...


I had to slam that hammervalve pretty hard, with an actual hammer to get it to fire.So that would be hard to use in a cannon.


But it...prooves...that some QEV's can take 850 psi for a while ...without raining parts.

Posted: Sun Mar 29, 2009 3:11 am
by john bunsenburner
inonickname wrote:You could really use any cylinder filled to insane pressure..HPA/scuba..etc
And regulate the pressure up?!

To have 10 000psi, and without soem insane construction, you need a tank or compressor, or another gas source with that out put pressure, you cannot, to my knowlage, take a 3000psi scuba tank and get a third of the volume of air at 9000psi...sadly...(again, this is to my knowlage, and without some insane construction)

Posted: Sun Mar 29, 2009 11:12 am
by sputnick
Yes john that is correct, regulators cannot create pressure, only reduce it. You need a pump to create pressure, but I doubt many people here would have the means to pump that much pressure, and even those probably don't own the systems themselves,I think the purpose of buying this QEV would be that they could feel 100% safe running whatever pressure they can achieve through it.

Posted: Sun Mar 29, 2009 12:04 pm
by ALIHISGREAT
Have we got a price for this yet?

Posted: Sun Mar 29, 2009 1:32 pm
by Big-E
Honestly, don't you think that that pneumatic pressures that high are a bit overkill? Even the biggest precharged pneumatic rifles (like the career dragonslayer 50 cal) are only pressurized to about 2000-3000 PSI. If you can drop a deer or larger game with one (which is what they are made for) then why even bother thinking of using pressures that are DOUBLE that? Barring purpose-built lab or industrial equipment, I don't see the point of running such a high pressure in a pneumatic. Sure, it's cool to theorize, but such high pressures make it a bit of a stretch for the typical builder; Even scuba cylinders aren't made to be pressurized that much.

At that point, I'd just consider getting a commercial PCP rifle, it'd be cheaper in the long run. I mean, once you go past a certian point, a pneumatic starts to become inneficient, and the construction materials and tolerances required would become cost-prohibitive.

Posted: Sun Mar 29, 2009 2:00 pm
by CpTn_lAw
The more pressure, the more acceleration...and the more fun. I think it sums it up. even if 6,000 psi is way overkill, if it can be done, why not give it a try?
I think i'm talking for everyone here if i say that, i wouldn't buy something that already exists if I can make it with a little effort. I say little because when you like doing something, a mountain of work can be just a little obstacle to achieving your goal. And, seeing some of the things that were made here on spudfiles, is the proof.

Posted: Sun Mar 29, 2009 2:05 pm
by D_Hall
Big-E wrote:Barring purpose-built lab or industrial equipment,
Which is exactly what brings me to these forums. I use the small scale stuff in my garage to learn about large scale stuff I deal with at work.

Posted: Sun Mar 29, 2009 2:19 pm
by Gippeto
CpTn_lAw wrote:The more pressure, the more acceleration...and the more fun. I think it sums it up. even if 6,000 psi is way overkill, if it can be done, why not give it a try?
I think i'm talking for everyone here if i say that, i wouldn't buy something that already exists if I can make it with a little effort. I say little because when you like doing something, a mountain of work can be just a little obstacle to achieving your goal. And, seeing some of the things that were made here on spudfiles, is the proof.
Indeed! :)

And I've yet to see a commercial PCP with 800-1000ft.lb potential.

Posted: Sun Mar 29, 2009 3:40 pm
by POLAND_SPUD
why even bother thinking of using pressures that are DOUBLE that?
for fun :-D

alternative version..

becasue we want MOAR power!!!


I agree with you to some extent.. we don't need one rated to 10000 psi... 3000 psi would be enough :wink:

Posted: Sun Mar 29, 2009 3:47 pm
by frankrede
Big-E wrote:Honestly, don't you think that that pneumatic pressures that high are a bit overkill? Even the biggest precharged pneumatic rifles (like the career dragonslayer 50 cal) are only pressurized to about 2000-3000 PSI. If you can drop a deer or larger game with one (which is what they are made for) then why even bother thinking of using pressures that are DOUBLE that? Barring purpose-built lab or industrial equipment, I don't see the point of running such a high pressure in a pneumatic. Sure, it's cool to theorize, but such high pressures make it a bit of a stretch for the typical builder; Even scuba cylinders aren't made to be pressurized that much.

At that point, I'd just consider getting a commercial PCP rifle, it'd be cheaper in the long run. I mean, once you go past a certian point, a pneumatic starts to become inneficient, and the construction materials and tolerances required would become cost-prohibitive.
2 years ago the idea of a 200x hybrid would have been laughed upon.

Posted: Mon Mar 30, 2009 3:23 am
by john bunsenburner
For the sake of it let my correct you. We are talking about pressures upto 5 times as high as 2000-3000psi.
And yes to a certain degree you are correct, and i doub each and every one of us will go boil liquid nitrogen and buy this QEV along with a sh*t load of redicilously highly rated steel pipe. But some will give it a try and god knows, perhaps and a few years the "normal" pressure people will be using will be well over 600psi and every experience builed wil have built atleast oen or two guns that do over 6000psi. It is doable, and i guess that if using a QEV then the whole gun(assumign the QEV costs around 300$) can be kept under 800$ or so.(Then again there is the question where to ge tthe pressure...)

Posted: Mon Mar 30, 2009 4:24 am
by jackssmirkingrevenge
Gippeto wrote:And I've yet to see a commercial PCP with 800-1000ft.lb potential.
There is this 20mm beast, 1140 ft/lbs ;) Not sure if it's a one-off or if it's commercially available though.

Posted: Mon Mar 30, 2009 5:51 am
by inonickname
Sorry, I must have been mistaken on the standard pressure of scuba bottles then. Though I am positive that cylinders (such as industrial ones- oxygen for oxy acet. for example) are available in suitable pressures..of course you'd aim for a light gas..and sourcing a regulator would be an issue. Most regulators for these kinds of applications are a low pressure output..oh well

the moar the better.

Posted: Mon Mar 30, 2009 9:30 am
by Big-E
I think your correct on industrial gas bottles, they can probably handle a lot more pressure, but I may be underestimating scuba tanks as well, seeing as they are used underwater primarily (I neglected to factor that in... My bad)

I wasn't trying to deter anyone from trying anything, just making a comment; By all means, if you can run pressures that high, go for it. I'd just be paranoid working with such high pressures; I don't want anybody to die from shrapnel, that's all. Heck, I've known people who've lost fingers to tiny streams of hydraulic fluid when working as diesel mechanics. high pressures can killl, no matter what the application

But if you can make a pneumatic that operates at such high pressures, and do it safely, well I'd be just as interested in seeing the results of such a build :D
jackssmirkingrevenge wrote:
Gippeto wrote:And I've yet to see a commercial PCP with 800-1000ft.lb potential.
There is this 20mm beast, 1140 ft/lbs ;) Not sure if it's a one-off or if it's commercially available though.
Yea, I've seen that before, I don't think it's a one-off, it's a big-bore airgun that's made to order. I believe you can get them though a guy called Big bore Bob http://www.bigborebob.com/ it's actually a modified quackenbush airgun if i'm not mistaken. Made to drop buffalo or other big game. A big bore conversion and tune from him (specificaly, the Quackenbush 308 bandit) can yield 900+ ft.Lbs. of energy from a projectile! Yikes!

Honestly, there are some guys that mod commercially available airguns to a point that would litterally knock your socks off (and that's if you're the one firing it!)

Posted: Mon Mar 30, 2009 2:04 pm
by Gippeto
A big bore conversion and tune from him (specificaly, the Quackenbush 308 bandit) can yield 900+ ft.Lbs. of energy from a projectile! Yikes!
Nope. That's 900fps for the 308 bandit. And around 500ft.lb for the .50cal.

Not even close.

high pressures can killl, no matter what the application
The simple truth :!:

The 20mm was designed and built with production in mind, but so far has not made it there.

Welding gas bottles have different pressure handling abilities. Most are rated for a service pressure of 3000psi. The highest I can special order locally, is 10 000psi nitrogen.

My N2 set me back nearly $300.

The regulators to handle the pressure, with high outlet pressures, will cost you big coin. I was VERY fortunate to find a used one for $60 on ebay, and I happen to overhaul the things for a living, so repair and re-ranging was easy for me. Even buying through my work, new cost would have been over $600.

I wouldn't count on many people forking out the dough to use these kinds of pressures any time soon. For the most part, I can see un regulated CO2, or regulated HPA with paintball equipment, being the upper end of the practical pressure range.


And that...is my .02 :)