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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.
WyldOne
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Sat Dec 20, 2008 4:16 am

G'day guys,

I'm looking at making a pneumatic gun.

I'm a bit confused on all this, but what I am wanting to make is a gun with a longish barrel, ammo will be 3-6mm ball bearings, I want it to be quite powerful and I'm looking at using a fire extinguisher or something as an air chamber thing.

I dont know what questions i should ask cause ive got like a million things going into my head but could yours please give me some ideas.. sorry if im confsuing yours too
raptorforce
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Sat Dec 20, 2008 4:25 am

look at some other poeple's designs see what they have done and either modify theres or think of your own
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cheeseboy
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Sat Dec 20, 2008 4:37 am

we don't like to spoonfeed you info, here we provide the information but do not really respond to people asking for plans and such, learn to always search before asking. but the best thing for you to look at would be the bbmg/ strafer showcase, for your first cannon disregard the bbmgs and vortex's and make a bb sniper with a 1/4' QEV and a 1/4" brakeline as a barrel. the other option is a cloud, search around to find out more about them as I don't make clouds.
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starman
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Sat Dec 20, 2008 5:05 am

WyldOne wrote:I dont know what questions i should ask cause ive got like a million things going into my head but could yours please give me some ideas.. sorry if im confsuing yours too
Then you haven't completed near enough study and preparation. Stick around and make good use of the showcases and search tool. Believe me, everything you need to know is here for the finding.

Also check out the stickies that are posted at the tops of all the forums.
WyldOne
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Sat Dec 20, 2008 6:37 am

Also, which type of valves are the best? I'm after one that doesn't loose much power.

I'm looking at making my gun similar to these:
Image

Image
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CasinoVanart
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Sat Dec 20, 2008 6:45 am

Piston valves are the best imo. You wont find them on the examples you have shown though.
WyldOne
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Sat Dec 20, 2008 7:02 am

Also, would a fire extinguisher (small one 1-4kg i'll probably buy) hold a large volume of air? I want my gun to be quite powerful rember.

is there anything on the net that explains the difference between types of valves??
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jackssmirkingrevenge
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Sat Dec 20, 2008 7:15 am

WyldOne wrote:I'm a bit confused on all this, but what I am wanting to make is a gun with a longish barrel, ammo will be 3-6mm ball bearings, I want it to be quite powerful and I'm looking at using a fire extinguisher or something as an air chamber thing.
That's not very detailed in terms of specifications.

Do you want to fire one shot every time you fill the tank, or do you want more shots per fill? What sort of pump or compressor do you have to fill it with? Are you looking to fire single shots, or fully automatic?
WyldOne
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Sat Dec 20, 2008 7:23 am

jackssmirkingrevenge wrote:
WyldOne wrote:I'm a bit confused on all this, but what I am wanting to make is a gun with a longish barrel, ammo will be 3-6mm ball bearings, I want it to be quite powerful and I'm looking at using a fire extinguisher or something as an air chamber thing.
That's not very detailed in terms of specifications.

Do you want to fire one shot every time you fill the tank, or do you want more shots per fill? What sort of pump or compressor do you have to fill it with? Are you looking to fire single shots, or fully automatic?
I know... I'm just confused on all the valves and stuff...

which one would be easier (in constructing the gun) as in automatic or single shot.

I'll be using a pump.
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jackssmirkingrevenge
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Sat Dec 20, 2008 7:52 am

Be aware that it will take you a while to pump it up manually, but let's say you get to 150 psi, that will give you a good amount of air for a BBMG. You can keep the original trigger on the fire extinguisher and fit a barrel and cloud chamber.

I made a very improvised variation of the idea here and got impressive results with low pressures and lightweight airsoft BBs, if you're using metal BBs at a higher pressure - I think 150 psi would be realstic for a good track pump - then you can make something much more destructive. It would be interesting to see a 3mm calibre BBMG, your air tank would last a lot more.
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inonickname
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Sat Dec 20, 2008 8:14 am

People seem to have problems with google and searching..

Ball valves are simple to use and cheap, but mostly you'll only get one shot (unless it's full auto/strafe). The problem with them is that the projectile has pretty much left the barrel before it's fully opened. You can use springs/elastic to help with this.

Modified sprinkler valves are basically sprinkler solenoids with the electrical component removed and a blowgun or similar valve used to pilot the diaphragm. Faster opening but more expensive and complex.

Then you have things like qev's, and then blow forward breeches, piston co-axials etc. Which are probably out of reach for your first time build.


Go to the BBMG/Strafer section and look at some of the CLOUD designs there. Fairly simple and sort of what you want. I'd probably leave a vortex alone for now.
WyldOne
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Sat Dec 20, 2008 8:18 am

jackssmirkingrevenge wrote:Be aware that it will take you a while to pump it up manually, but let's say you get to 150 psi, that will give you a good amount of air for a BBMG. You can keep the original trigger on the fire extinguisher and fit a barrel and cloud chamber.

I made a very improvised variation of the idea here and got impressive results with low pressures and lightweight airsoft BBs, if you're using metal BBs at a higher pressure - I think 150 psi would be realstic for a good track pump - then you can make something much more destructive. It would be interesting to see a 3mm calibre BBMG, your air tank would last a lot more.
Cheers mate! That is excellent help mate! Awesome gun by the way mate! Looks to be quite deadly too mate!

I don't mind spending a while pumping up the chamber. :D

Also, I'm leaning a bit more towards a single shot gun.

Which valve would best suit with what I want? As soon as I pull the trigger or whatever, I want the ammo flying out FAST and HARD! :D I don't want to loose too much air pressure. I want to keep the air pressure up to a maxium as soon as I hit the trigger.

Sorry if I'm confusing the bajebess out of yours...
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cheeseboy
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Sat Dec 20, 2008 8:39 am

the easiest way to do a single shot with which you don't have to compress the chamber before every shot is to have two chambers; a primary chamber and a secondary chamber. the primary chamber is large, and you fill it up with the compressor to the pressure you want each shot at, then when its pressurized you open a ball valve to the secondary chamber, which is then connected to the main valve, barrel and such. basically you have a reservoir of pressure that you pressurize the gun with, you can also use a hammer valve ... but since this topic is called "newbie" I won't describe it, hope this helps!

edit: oh.. for the main valve use a QEV connected to a blowgun, this gives you the best performance while still allowing you to have the traditional trigger grip.
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john bunsenburner
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Sat Dec 20, 2008 9:30 am

I am slightly confused here, do you want a BBMG(lots of shots per fill) or a single shot gun(refill after each shot), it makes a big difference!! The gun you showed, from what i can see is latter while clouds, vortextes and Jack^s gun are all BBMGs.
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SP00K
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Sat Dec 20, 2008 10:27 am

It is kind of a waste, but BIC pen tubes work wonders for 6mm ammo. (Dont know if I'm too late to say this or not)
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