Directing Pilot Volume Into Barrel

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jr
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Sat Feb 16, 2008 1:57 am

When a blow gun or other pilot valve is use the there is a small amount of air that is waisted. would there be a negative effect of dumping that air into the barrel? This could help eliminate some of the dead space,right?
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MrCrowley
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Sat Feb 16, 2008 2:01 am

You'd be wasting more power by trying to find a efficient way to direct the piloted air into the barrel.

Even if you did without losing power, it'd make sh|t all difference, the projectile would be long gone. :)
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jackssmirkingrevenge
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Sat Feb 16, 2008 2:17 am

The most practical way of eliminating waste in this area is to make sure your piston is a tight fit, or even better, 100% seal, as well as making sure your pilot volume isn't any bigger than it should be.
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MrCrowley
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Sat Feb 16, 2008 2:32 am

And if you're piloting a sprinkler valve or similar, keeping the pilot volume as small as possible would be better.
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Ragnarok
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Sat Feb 16, 2008 10:53 am

jr wrote:Would there be a negative effect of dumping that air into the barrel?
Yes, actually. It prevents the pilot volume's pressure completely falling to atmospheric, which may delay the valve opening.

Even if you could get it perfect, if your pilot volume is a sensible size, then it would do very little - less than adding the pilot volume on to the end of your chamber.

It's an old idea, but it's not really going to help. If it did, we'd all be doing it.
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Sat Feb 16, 2008 11:38 am

You would be better off using the burst of air from the pilot to power a small pneumatic ram to operate some sort of loading mechanism.
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STHORNE
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Sat Feb 16, 2008 11:43 am

don't even bother, its not enough energy to try to salvage and direct to the barrel
your better off just waisting it
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bigbob12345
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Sat Feb 16, 2008 11:53 am

Yes this would be a lot of effort and woulds actually deacrease performance by a noticable margin.
Although if you want to use the air coming out of the pilot put a barrel on the pilot I did that and I could fire a golf ball and paintball at the same time it is quite fun even though it may decrese performance of the valve a little.
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STHORNE
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Sat Feb 16, 2008 12:00 pm

yeah, i mean if you really tried, you could modify into something kewl like a 2nd barrel, otherwise it would just be a waist of time and money.

if you are considering doing something with that extra air, i suggest you do some research so you don't end up screwing yourself over
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bigbob12345
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Sat Feb 16, 2008 12:10 pm

Hawkeye wrote:You would be better off using the burst of air from the pilot to power a small pneumatic ram to operate some sort of loading mechanism.
I really like this idea.
Although it may be triky to set up it would give you easy semi auto.
I will probably try this and most likley fail.
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Pilgrimman
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Sat Feb 16, 2008 12:19 pm

Rag already pointed out the first problem, and here's the second: Thje air would push the projectile forward, and it wouldn't receive all of the high pressure air at once (hard to describe).
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spudy buddy
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Sat Feb 16, 2008 2:50 pm

ya it would push the projectile further down the barrel before the valve is opened thus creating dead space.
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Brian the brain
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Sun Feb 17, 2008 6:31 am

I think you would create a honker.If you accidentally get all dimensions right it would even be an auto valve.
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schmanman
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Sun Feb 17, 2008 9:22 am

bad idea.

I have seen the pilot volume used with a small diameter barrel before.
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