HEAL 320psi 20mm copper cannon (now with damage videos)
A mega light piston would help, but not by a lot. I know that HEAL's piston is fairly heavy, but the high pressures and opening forces, along with the piloting valve help negate that nicely.
Bigger is one way of going about it though.
Bigger is one way of going about it though.
- ALIHISGREAT
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i'm gussing no as the slide valve is the pilot
- Infernal Maveric
- Specialist 2
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Rag I know that beating a home-made 22mm piston won't be easy, but where I might lack in making a piston (I can, but choose not to) I will make up with the opening times. I am currently drawing up plans for my new gun that I would like to make. I will be a QEV burst-disk gun. sounds whacky but it's feasable.
Hmn..grease as the sealent..makes scense, but 300+ PSI wooshing through there, I'm sure a tiny bit of air would leak, im sure that an O-ring inserted at the back here the barrel slides into would increase preformance. Not toticable, but still by a bit.
Hmn..grease as the sealent..makes scense, but 300+ PSI wooshing through there, I'm sure a tiny bit of air would leak, im sure that an O-ring inserted at the back here the barrel slides into would increase preformance. Not toticable, but still by a bit.
Silicon grease is pretty good stuff, it will stay in place quite solidly.
It's not completely leak free at 300 psi, but it still holds damn well - the leaks at the breech are minuscule compared to the blow-by on many of my projectiles.
I wanted a pipe/fitting interface like I have at the moment to support the barrel as firmly as possible to help accuracy. The difficulty that arises is that there is no space for an O-ring in the fitting without constricting flow, negating the valve's high power.
So, I think adding an O-ring would likely reduce power, rather than help it.
Hmm, a QEV burst disc valve combo. That will easily win out on opening time, but I think flow would be lower.
@Wannabie: I could get multiple shots with an external gas source, but you could do that with most valves. Slide valves are better optimised for it though.
The main reason was that a slide valve will vent quicker than a blowgun, opening the pilot valve more cleanly, but the straight pull of the slide valve was tempting too.
It's not completely leak free at 300 psi, but it still holds damn well - the leaks at the breech are minuscule compared to the blow-by on many of my projectiles.
I wanted a pipe/fitting interface like I have at the moment to support the barrel as firmly as possible to help accuracy. The difficulty that arises is that there is no space for an O-ring in the fitting without constricting flow, negating the valve's high power.
So, I think adding an O-ring would likely reduce power, rather than help it.
Hmm, a QEV burst disc valve combo. That will easily win out on opening time, but I think flow would be lower.
@Wannabie: I could get multiple shots with an external gas source, but you could do that with most valves. Slide valves are better optimised for it though.
The main reason was that a slide valve will vent quicker than a blowgun, opening the pilot valve more cleanly, but the straight pull of the slide valve was tempting too.
- Infernal Maveric
- Specialist 2
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- Joined: Sat Oct 08, 2005 3:41 pm
Ah ok, I guess its better to have the flow out of the barrel more effienct than having it 100% air-tight around the breech.
I did originally try to find a way of fitting an O-ring into the slot where the solder would normally fit in the solder ring fitting at the breech (It is the only solder ring fitting on the launcher though, used only because of it's neat fit into the 28mm pipe the breech loader's made from.)
Didn't work out though.
It's quite interesting how much interest a topic can get with the words "320psi" and "copper" in the title.
Didn't work out though.
It's quite interesting how much interest a topic can get with the words "320psi" and "copper" in the title.
I don't think that it was the title as much as the name of the author of the thread that attracted all the views. Joanna talked quite a bit about you, and most of the senior members knew who you were.
Titles do help though, I posted a handheld gun that ran on 500 psi nitrogen and it only got 8 comments. ( It was a very simple design though).
Titles do help though, I posted a handheld gun that ran on 500 psi nitrogen and it only got 8 comments. ( It was a very simple design though).
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
It was just a random thing that I threw together with some parts I had around while working on my burst disk cannon. Here's a link
Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
please, please get some video footage
I really want to see something annihilated at 320psi
This is a sweet piece of work, if you live in England where do you shoot it with it being so loud and the distance of rounds?
If it had a stock and its bipod on and a large scope I bet it would feel like an m107 or similar.
Once again top job


This is a sweet piece of work, if you live in England where do you shoot it with it being so loud and the distance of rounds?
If it had a stock and its bipod on and a large scope I bet it would feel like an m107 or similar.
Once again top job

Always out numbered....
never out gunned
never out gunned