Upgraded Pneumatic Marble Sniper

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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zeigs spud
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Wed Mar 14, 2007 8:53 pm

noname wrote:It looks ghetto? I have no idea what you're talking about, that thing is awesome, and looks great. Soda bottles are rated to 160 psi, so you shouldn't have a problem anyway.
Why is the blowgun in that position? Looks kind of awkward to shoot like that.
yea same here....ummm all at 160 psi tho idk lol
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rna_duelers
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Thu Mar 15, 2007 6:02 am

Well I can say that Soda bottles when they explode they is relatively low energy transferd into the bottle plastic wall.I have had a 2.5L bottle explode in my face at 130psi and I only got a sore hand.The Bottles more rip then explode and they are neat rips not sharp edges that could cut you.

I have made a heap of these Soda Bottle chambers guns and they are awesome and cheap as hell they look pretty schmick aswell..Nice gun keep on shooting.
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spudthug
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Thu Mar 15, 2007 6:05 am

i trust soda bottle but not at 160 psi lol......id go 110 max and not risk my dang....but ur decision
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ilikeguns
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Wed Mar 21, 2007 5:47 am

how did u attach the ball valve to the bottle? im making something similar to this but my 20 mm ball valve doesn't fit on the bottle
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Mitchza89
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Wed Mar 21, 2007 5:50 am

I just filled off the old thread on the bottle untill it was flat. I then slowly turned the ball valve onto it. It cut a new thread onto the bottle that matched perfectly.

Regards,

Mitch.
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jackssmirkingrevenge
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Wed Mar 21, 2007 5:59 am

I used to work in a softdrinks factory in Quality Control, one of the tests on the PET line was to take a sample bottle from each blowmoulding station and attach it to a device that filled it with water to the correct fill height, then pressurised the headspace with nitrogen.

Typical burst pressures for 0.5 litre iced tea bottles was around 305 psi, and around 185 psi for 1.5 litre bottles. We didn't make carbonated drinks in plastic bottles, but presumably they would be even stronger than that. It's also important to note that due to the manufacturing process, some bottles are going to be stronger than others.

The beauty of PET bottles is that they rupture, not shatter, with no potentially dangerous fragments.
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ilikeguns
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Wed Mar 21, 2007 6:00 am

ok thanks allot now i can finally finish mine :D also very nice gun looks great.
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Mitchza89
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Wed Mar 21, 2007 6:06 am

Haha thanks alot for that. Yeah I'm about to make a Barrel-Sealing Piston Valve out of Irrigation parts and Galvanised Steel with a PET Bottle chamber. It should look pretty different =P
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CpTn_lAw
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Wed Mar 21, 2007 6:25 am

rna_duelers wrote:Well I can say that Soda bottles when they explode they is relatively low energy transferd into the bottle plastic wall.I have had a 2.5L bottle explode in my face at 130psi and I only got a sore hand.The Bottles more rip then explode and they are neat rips not sharp edges that could cut you.

I have made a heap of these Soda Bottle chambers guns and they are awesome and cheap as hell they look pretty schmick aswell..Nice gun keep on shooting.

I wouldn't be so sure about that...My brother's pneumatic exploded in it's hands, causing major cuts and 2 days deafening. (the bottle had been used for a loong time at 60 psi and exploded at 40) bottles are made for handling pressure of 80 psi in a small area. When it's the whole bottle that is pressurized, it slowly deforms itself, causing little decrease in pressure resistance.
I trust metal since this afternoon when my brother came and said "i can't hear you...i'm cut." and i saw his mouth bleeding, and his hand.
Do what you want to do, but a 2" by 1' of gal. steel pipe is a lot more sure than a plastic soda bottle.
brother361
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Tue Nov 06, 2007 3:37 pm

did the bottle just screw into the bal valve
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Mitchza89
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Tue Nov 06, 2007 10:42 pm

Yeah it sure did. I filed the old thread off the bottle and screwed on the ball valve with brute force. That in return, cut a new thread into the bottle.
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