Marble Machine Gun

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.
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demilus
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Fri Aug 24, 2007 12:02 pm

Hey, I have a couple of questions/ideas that I would like to bounce off you guys.

My design is for a burst/full-auto marble gun. It's relatively simple. Look at the picture first.

Should I sleeve the copper into PVC, or should I bore out a copper tee and slide the barrel through?

Also, and this is the main question, what should I use to keep the marbles from rolling out?

I've thought of cutting a notch then putting a wedge of rubber in the notch to hold them back. Or even just cutting a notch right below the mag. I'm just worried about weakening the copper too much.

Your ideas are greatly appreciated.
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My basic design.
My basic design.
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jackssmirkingrevenge
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Fri Aug 24, 2007 12:08 pm

hectmarr wrote:You have to make many weapons, because this field is long and short life
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demilus
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Fri Aug 24, 2007 12:25 pm

Well, thanks for that link jack. I suppose I will go with the tooth brush bristle idea. Any idea as to how high of pressures hot glue would go up to on copper pipe? Or should I use epoxy?

BTW the sarcasm wasn't necessary, as the search button isn't always reliable, but thanks for the link anyway.
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jackssmirkingrevenge
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Fri Aug 24, 2007 12:57 pm

It's Friday, I can :)

Seriously, didn't mean to be offensive, just making a general point. There should be a how-to on searching.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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demilus
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Fri Aug 24, 2007 1:04 pm

Haha, that's one of the funniest things I've heard in a while. That's actually a good idea, a lot of people could benefit from that.

Oh man, I read that and I just started cracking up.
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MisterSteve124
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Fri Aug 24, 2007 1:44 pm

How is it going to be full auto or even semi auto using a sprinkler valve? You'd need a continuos source of air.
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demilus
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Fri Aug 24, 2007 1:53 pm

That's basically it right there. I'm going to have a very large air tank, and also it will be filled using a regualted HPA tank. So all in all, lots of air through a small hole. It won't empty like a regular gun since it's only a 1/2" barrel to a large chamber. Barrel choke takes a big role here.
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potatoflinger
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Fri Aug 24, 2007 4:27 pm

jackssmirkingrevenge wrote:It's Friday, I can :)

Seriously, didn't mean to be offensive, just making a general point. There should be a how-to on searching.
But how would people find it?
It's hard to soar with eagles when you're working with turkeys.
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MrCrowley
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Fri Aug 24, 2007 5:16 pm

MisterSteve124 wrote:How is it going to be full auto or even semi auto using a sprinkler valve? You'd need a continuos source of air.
You can use semi-auto with a sprinkler valve if you have one helluva compressor tank.
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frankrede
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Fri Aug 24, 2007 5:35 pm

MrCrowley wrote:
MisterSteve124 wrote:How is it going to be full auto or even semi auto using a sprinkler valve? You'd need a continuos source of air.
You can use semi-auto with a sprinkler valve if you have one helluva compressor tank.
True. I have done it.
The ROF was crap but thats because I had a over sized chamber.
But I imagine if I had a 50% smaller chamber the ROF could go up.
I believe alot of it had to with constriction of flow. My hose was 100' and the 1/4" connections were chocking.
I should throw on my 1/2" hose+ 3/8" disconnects, I could imagine it would shoot as fast as fast as I could get the valve to reseal.

Note: I realize that there is alot of flow consticion before the hose too.
the regulators+ all the "doohickeys" are all a problem.
Oh well.
Current project: Afghanistan deployment
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beebs111
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Fri Aug 24, 2007 10:39 pm

demilus wrote:Any idea as to how high of pressures hot glue would go up to on copper pipe? Or should I use epoxy?
youre not going to use hot glue to cement the pipe together are you? im not sure if you are referring to holding bristles in place or to connect the pipe. if you want to connect a pipe with hot glue, then i will not say anything and just let nature take it's course, we will all be better off.
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jackssmirkingrevenge
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Sat Aug 25, 2007 2:20 am

potatoflinger wrote:
jackssmirkingrevenge wrote:It's Friday, I can :)

Seriously, didn't mean to be offensive, just making a general point. There should be a how-to on searching.
But how would people find it?
priceless :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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frankrede
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Sat Aug 25, 2007 4:01 am

jackssmirkingrevenge wrote:
potatoflinger wrote:
jackssmirkingrevenge wrote:It's Friday, I can :)

Seriously, didn't mean to be offensive, just making a general point. There should be a how-to on searching.
But how would people find it?
priceless :D
I lol'd.
Current project: Afghanistan deployment
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spud yeti
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Sat Aug 25, 2007 5:02 am

jackssmirkingrevenge wrote:
potatoflinger wrote:
jackssmirkingrevenge wrote:It's Friday, I can :)

Seriously, didn't mean to be offensive, just making a general point. There should be a how-to on searching.
But how would people find it?
priceless :D
search for the how-to :D :D
really good quote/phrase here
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demilus
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Sat Aug 25, 2007 8:27 am

No, I'm not referring to hotgluing the pipe together :lol: . I was referring to the bristles. It just seemed like hotglueing the bristles in would lead to them getting popped out.
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