Need better pilot valve

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spudkpi
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Tue Apr 13, 2010 9:04 pm

But a ball valve would have to be manually actuated and then re-closed? How is that semi-auto? See with the blowgun I can push it and then immediately release it and the pressure goes back up. I think I'm just confused and need a visual aid from one of you guys if your willing. I want semi-auto like shot shot shot. Where I could have a magazine feed steel shot into the barrel and whenever I pull the "trigger" it shoots. With a bal valve won't I hav e to open and re-close it? Keep in mind I am running this off of a regged co2 tank.


http://www.spudfiles.com/forums/the-1-4 ... 20693.html


I am just getting confused I think. I am going to make the pilot smaller bu shortening the nipple between the QEV and the chamber but how do I do this :lol:
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chinnerz
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Tue Apr 13, 2010 9:12 pm

nope, i dont think i have ever seen/ is possible, to have a ball valve in a semi.
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spudkpi
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Tue Apr 13, 2010 9:16 pm

I think what I'm going for is too much of a semi/auto deal here. I want it to fire as fast as I can pull the trigger really and I just don;t think it's possible with this setup. I might just keep it simple and open the valve to fill the chamber then close it then fire then reload and do the same thing. I'm not sure of any other way to do it. I cannot have the co2 run directing into the chamber can I? Will it just pour out of the pilot? I'm just pumped I have the reglateduco2 for portability reasons.
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jackssmirkingrevenge
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Tue Apr 13, 2010 9:49 pm

spudkpi wrote:But a ball valve would have to be manually actuated and then re-closed?
That's why we suggested you spring load it, so that when released it automatically returns to the closed position.
I cannot have the co2 run directing into the chamber can I?
With a suitably modded QEV (spring behind the piston and a small equalisation hole like brian did here) then yes.

Don't forget that adding a pop-off valve to your QEV gives you full auto ;) add a BB hopper like I did here and you're sorted :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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spudkpi
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Tue Apr 13, 2010 9:58 pm

I thought about the full auto for a while with the pop-off but I think that's overkill for what I am wanting to do. Eventually this gun will shoot 1/4" steel slingshot ammo. And I searched for a spring loaded ball valve and could not find it? Any help on that?
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jackssmirkingrevenge
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Tue Apr 13, 2010 10:09 pm

spudkpi wrote:I searched for a spring loaded ball valve and could not find it? Any help on that?
FighterAce uses them as a main valve, other examples here and here some have also suggested the use of rat trap springs.

All the above examples though are ways of opening a ball valve with a spring. You would have to configure it in the opposite manner, with a spring that closes the ball valve when you release it, it really shouldn't be that hard to do.

...or you could always pilot with a schrader ;)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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spudkpi
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Tue Apr 13, 2010 10:20 pm

I am not so sure that a schrader would pilot it enough. My pilot volume is too large right now I think. I think what I might do is try to go the spring loaded QEV route and see if I could just bypass all this shit and put a spring behind the QEV diaphragm and see what happens. I just want this to be able to be shot after shot without manually opening and closing a ball valve. I could however just make it to where the ball valve is spring closed back into position and just hand cranked open for a quick fill then go from there. This is all very hard to do when you want it to keep the shape of a gun and not some contraption...
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spudkpi
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Tue Apr 13, 2010 10:43 pm

Its going to be too hard to keep this in the shape of a gun with all the regulator and ball valve setup I think.
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jackssmirkingrevenge
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Tue Apr 13, 2010 11:10 pm

If you want the high pressure equivalent of a blow-gun you could always try a pressure washer gun.
Its going to be too hard to keep this in the shape of a gun with all the regulator and ball valve setup I think.
Pretty is as pretty does, there are many effective firearms out there that don't look like they "should" ;)

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hectmarr wrote:You have to make many weapons, because this field is long and short life
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spudkpi
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Tue Apr 13, 2010 11:23 pm

THis has all definitely helped but we'll have to hit up the home depot tomorrow and get some elbows and maybe tees to make this think worthy if at all. Thing that is killin gme is that I have the delicious flavor of regged co2 and i can't harness the power!
EvilFish
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Wed Apr 14, 2010 12:06 am

Nice gun JSR, but have you seen my coffee machine?
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jackssmirkingrevenge
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Wed Apr 14, 2010 12:15 am

If I was faced with that thing in the morning, I'd probably shoot it :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
EvilFish
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Wed Apr 14, 2010 12:25 am

or maybe just KILL IT WITH FIRE!!!
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Matt_NZ
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Wed Apr 14, 2010 1:07 am

jackssmirkingrevenge wrote:
Gun Freak wrote:My 1/4 ball valve is amazingly easy to turn, with just one drop of 3in 1 oil on each side of the ball.
I would recommend such lubrication over extensive drill-spinning in order to preserve the integrity of the seal, especially for higher pressures.
This might sound like a stupid question, but could there be a risk of the lubricant exploding under pressure.
I've heard of such paintball tanks exploding from oil in the fill valve.
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chinnerz
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Wed Apr 14, 2010 1:20 am

i highly doubt that -_-'
the oil i would use, (some cheap hobby glue and some engine grease) dont burn at all (much to my disappointment)
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