Just a little something I've been playing with, same old pengun design but using new materials.
I upped the calibre to 0.22", a bit overambitious and the 10mm internal diameter of the body tube does not allow for much air but still, it will happily push a 16 grain pellet through a beer can. Here it is in action at 300 psi:
[youtube][/youtube]
Posted: Sun Oct 28, 2012 3:11 am
by pneumaticcannons
Thats looks so awesome
So is the body re-enforced or completely CF?
Posted: Sun Oct 28, 2012 5:54 am
by wyz2285
Beautiful.
A 4.5 mm at 200 bar wound make this thing a serious killer
Posted: Sun Oct 28, 2012 7:06 am
by Labtecpower
ohh fap
that looks damn sexy
If you send a vid and some pictures to the producers of the James Bond movies you might even get a serious response, this wouldn't look bad in an Aston Martin
Posted: Sun Oct 28, 2012 7:24 am
by jackssmirkingrevenge
Cheers guys
pneumaticcannons wrote:So is the body re-enforced or completely CF?
A 4.5 mm at 200 bar would make this thing a serious killer
I don't know if I'd trust this one with that pressure, but there's definitely scope for a 200-300 bar pengun...
If you send a vid and some pictures to the producers of the James Bond movies you might even get a serious response, this wouldn't look bad in an Aston Martin
Why would I want that bender using my stuff
Posted: Sun Oct 28, 2012 7:42 am
by pneumaticcannons
No, pure CF tube. This stuff.
Just had a "why didn't I think of that" moment. I mean, those arms are perfect; robust, sexy, and practically made of epoxy. made of epoxy made of epoxy
Posted: Sun Oct 28, 2012 8:18 am
by Brian the brain
Looks awsome!
I have owned commercial airguns ( pistol) with about the same performance...
With your machining abilities ....couldn't you get the most out of the concept by using hydraulic tubing?
Perhaps use an O-ringed sliding barrel as your valve, sealing against a rubber backplate...that would make it balanced so you could easily trigger it at high pressure...
Posted: Sun Oct 28, 2012 10:57 am
by sagthegreat
holy crap, a legit pen, except machined out of high pressure steel, go up to 1000 psi, OMG this has soo much potential
Posted: Sun Oct 28, 2012 12:37 pm
by jackssmirkingrevenge
pneumaticcannons wrote:practically made of epoxy. made of epoxy made of epoxy
... and loosely packed diamonds
I have owned commercial airguns ( pistol) with about the same performance...
... and this is at just 300 psi! Tried it at 400 and it leaked :-/
With your machining abilities ....couldn't you get the most out of the concept by using hydraulic tubing?
The little sherline doesn't really like steel, but there's no reason why a sufficiently thick walled brass or aluminium small bore tube couldn't safely take 300 bar.
Perhaps use an O-ringed sliding barrel as your valve, sealing against a rubber backplate...that would make it balanced so you could easily trigger it at high pressure...
I had some ideas for a "valveless" variation:
The problem is that at those pressures, it's going to be bloody hard to trigger. Past 300-400 psi the ballistic knife is almost impossible to operate. On the other hand, that's with a 13mm bore and 1.32 cm<sup>2</sup> surface area. With a 4.5mm projectile, the area drops to just 0.159 cm<sup>2</sup>... so extrapolating that, if 300 psi is fine for the knife, then a BB firing pengun is good for 2500 psi... the seal fitment is a bit tricky for a spherical projectile though.
Posted: Sun Oct 28, 2012 2:00 pm
by POLAND_SPUD
now that you have a lathe you could experiment with metal on metal seals
while wouldn't be exactly very useful for pneumatics it has some potential for hybrids (especially for cartridge hybrids)
Posted: Sun Oct 28, 2012 2:44 pm
by jackssmirkingrevenge
Note that the first diagram in my previous post doesn't have a separate seal but uses a lead projectile, I think this could be made to work for HPA.
Posted: Sun Oct 28, 2012 2:56 pm
by POLAND_SPUD
are you assuming that pellet skirts can expand on their own to form a seal ? I don't think that's really what you meant.
Probably one would have to use swaging to make sure the projectile is sealed tightly
Posted: Sun Oct 28, 2012 3:23 pm
by jackssmirkingrevenge
Some form of swaging is obviously needed, but the shape of the skirt should help.
Remember this?
[youtube][/youtube]
It definitely works for lower pressures...
Posted: Sun Oct 28, 2012 3:43 pm
by POLAND_SPUD
actually I don't
not bad so there was some testing done
but if it works for lower pressures wouldn't it work for higher pressures if there was a funnel shapped port (ie basicly a constriction) ?
