Large caliber bbmg unregulated CO2

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.

Will this be safe?

depends on wether or not you're the target
5
56%
Nope
0
No votes
Perfectly safe for kids over 5 yrs of age ( muhahaha)
4
44%
 
Total votes: 9
iknowmy3tables
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Tue Oct 16, 2007 3:37 pm

I say use 3000psi Nitrogen regulated (palmer time) to 800psi
and machine that vortex block out of solid metal

however why not go basic first with a cloud high presure clouds have been done before
by the way that feed spring will have to be pretty strong
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windshrike
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Tue Oct 16, 2007 3:37 pm

Well, to save CO2, I'm going to mention an idea I had a while ago. How about using a small piston valve to supply air to your vortex block? That would regulate the amount of gas used and give very consistent burst fire. Come on, we all occasionally have the urge to make a "burst" last as long as it can.
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goose_man
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Tue Oct 16, 2007 4:05 pm

I like this idea a lot. Imagine even bigger steel ball bearings... :twisted:

When it's made, damage shots would probably look insane...

-goose_man
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Tue Oct 16, 2007 4:22 pm

Brian the brain wrote:I was referring to the main valve on a bottle.

Do valves on a CO2 fire extinguisher ever freeze up??
I am confident the valve will work..
Notice that both the valves you mention are engineered and built to come in contact with CO2.
My main concern with your valve it that it is not intended to come in contact with anything more thermodynamically demanding than liquid water.
I am in full support of the idea, it is pretty cool. Us spudders just gotta look out for our own. :wink:
How does liquid pressure behave differently??
In a liquid there is not enough energy for the molecules to overcome the intermolecular force that is holding them together. Because of this, they cannot travel in the random strait line motion that they love so much, at least not for as far as they would like. Therefore liquids will not expand (much) given a sudden opportunity to. In summation, you just gotta watch out for a violent release of gas. (Think explosion)
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jackssmirkingrevenge
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Tue Oct 16, 2007 10:55 pm

iknowmy3tables wrote:by the way that feed spring will have to be pretty strong
I though the piston wasn't airtight meaning the gas pressure on both sides of the piston cancelled out? It might be feeding larger bearings but weight for weight it should be under the same stresses as feeding a larger quantity of smaller BBs.
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ammosmoke
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Tue Oct 16, 2007 11:30 pm

Its like liquid propane vs. gaseous. Gas airsoft guns get their power from the heat absorbing properties of liquid propane, ie expansion. When the gun releases liquid, it rapidly expands into gas as it absorbs the heat and the molecules move as they would normally. So, when you let out liquified gas, it creates rapid pressure spikes. The amount of gas contained in liquid form is much greater per square in, than in gaseous form. So yeah, rapid spike.

Edit:
jackssmirkingrevenge wrote:
iknowmy3tables wrote:by the way that feed spring will have to be pretty strong
I though the piston wasn't airtight meaning the gas pressure on both sides of the piston cancelled out? It might be feeding larger bearings but weight for weight it should be under the same stresses as feeding a larger quantity of smaller BBs.
I think he just meant that it would push it back, even if it were to be empty.
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f.c
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Wed Oct 17, 2007 4:15 am

its actually an ingenious idea. imagine the destruction you could cause with it. but unregulated co2 might not last very long. but you are brian the brain and i have seen some amazing work from you so go ahead.
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Wed Oct 17, 2007 10:18 am

Wow Brian, I really like this idea :D

Please add a longer barrel though, it may not look as cool but it will sure as hell make it more powerfull. I have had an idea recently that seems to fit this design because of the metal ammo used.

You know how adding something in the barrel of a normal strafer that puts pressure on the bb's to shoot them at a higher velocity? Well why not apply the same princible to this bbmg with powerfull magnets? Get some super magnets from the inside of an old pc hard drive and stick them at the base of your barrel. I have a feeling this will make it more powerfull :twisted:

Good luck!
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Wed Oct 17, 2007 12:47 pm

)Demon(, somethings such as an o-ring will temporarily block the projectile, then suddenly and completely release it. A magnet's force acts over a distance, so you do not get a sudden release. I would imagine that a magnet would do nothing to help velocity.
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beebs111
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Wed Oct 17, 2007 7:25 pm

if you used an non-magnetic material for the barell then i would imagine it would be like a burst disk affect, holding the ammunition in place untill a certian pressure is reached, at which point it is released, allowing all of that built up pressure to push it out of the barrell, if i am thinking correctly.
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Wed Oct 17, 2007 8:28 pm

I do not believe you are, since there will be no sudden release of the ammo. You would need a pulsing electromagnet to that I'd think.
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windshrike
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Wed Oct 17, 2007 8:45 pm

Has not anyone considered my idea of a piston valve being used to feed air to the vortex block? It would provide relatively short, controlled bursts and regulate the amount of CO2 used.
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Wed Oct 17, 2007 8:46 pm

On the note of silencers, that you talked about in your first post, i dont think the standard spudgun silencer would work. they work by absorbing some of the air, then dumping it back out slower than it was originally released. this doesnt work however, when you have a continuous stream of air. Instead of having a big silencer, all you need is a system of baffles, or better yet, a bunch of industrial silencers for pneumatics (the type they sell at mcMasters, called exhaust mufflers or something like that) attached to the holes that would otherwise be drilled for the silencer. These suppress continuous streams of air, as opposed to spudgun silencers.

thats my input, what do you all think?
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jackssmirkingrevenge
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Wed Oct 17, 2007 10:29 pm

Lentamentalisk wrote:On the note of silencers, that you talked about in your first post, i dont think the standard spudgun silencer would work. they work by absorbing some of the air, then dumping it back out slower than it was originally released. this doesnt work however, when you have a continuous stream of air. Instead of having a big silencer, all you need is a system of baffles, or better yet, a bunch of industrial silencers for pneumatics (the type they sell at mcMasters, called exhaust mufflers or something like that) attached to the holes that would otherwise be drilled for the silencer. These suppress continuous streams of air, as opposed to spudgun silencers.
The fact that you're adding projectiles into the mix means that the air isn't a continuous stream but it's being pulsed.

Also, take a look at an automotive muffler, made for what is practically a constant flow of exhaust:

Image

It's really the same combination of perforated pipe and expansion chamber as most spudgun silencers.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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ammosmoke
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Fri Oct 19, 2007 11:40 pm

I just thought of this during school for some reason... Why not use a venturi tube to increase velocity and the ability to draw bb's? (At least smoothly anyways...) You know where its basically a smoothly tapered funnel? Air or liquids accelerate when put into a smaller space so.... If you were to make the path better it may make improvements...
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