Au contraire, I think we're mostly quite reasonable, and only to happy to share advice based on our own experiences and research. If this happens to disagree with what you believe, that can hardly be construed to be impolite. This is a discussion forum, there'd be no discussion if we all agreed all the timegabeb123 wrote:hey you guys are all so hostile chill out.
rebuilding
- jackssmirkingrevenge
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- MrCrowley
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If good means efficient, no.gabeb123 wrote:good point.
hey so i got a 1.5"pvc barrel that is about 4 feet long and a 3" chamber that is 33 inches long is that good
Cut the chamber down to 12"-15", that's all you'll need.
- Technician1002
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For very low pressure stuff such as 6-10 PSI, the ratio is good and effecient. For very low pressure cannons, a very fast valve is not required. A well lubed ball valve provides good flow.MrCrowley wrote:If good means efficient, no.gabeb123 wrote:good point.
hey so i got a 1.5"pvc barrel that is about 4 feet long and a 3" chamber that is 33 inches long is that good
Cut the chamber down to 12"-15", that's all you'll need.
If you intend to use higher pressure then a smaller chamber will be needed for high effeciency. Use GGDT to model your chamber and barrel at your working pressure. An oversize chamber can provide a small velocity increase at the expense of using more than twice the air. For hand pumped stuff, smaller is much less work to pump up.
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It wont hurt performance, it will just waste air from your compressor, so if you're happy with that, leave the chamber at 33". Though you might have trouble if you use a track pump to pump it up.
Most sprinkler valves are rated to 125PSI, safe enough at 150PSI.
Most sprinkler valves are rated to 125PSI, safe enough at 150PSI.
- Technician1002
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I love screw on barrels. The ammo variety increase is fantastic.gabeb123 wrote:next im going to modify the sprinkler valve and im going to make a new bigger barrel for it im thinking 2" because i have tons of empty caulk tubs laying around.
- Willdebeers
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Nice paint job!Technician1002 wrote:I love screw on barrels. The ammo variety increase is fantastic.gabeb123 wrote:next im going to modify the sprinkler valve and im going to make a new bigger barrel for it im thinking 2" because i have tons of empty caulk tubs laying around.

- Willdebeers
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Nice. But what's the point of having threads when you only have one barrel?



