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2240 Valve mods

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Kris View Drop Down
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    Posted: 29 May 2025 at 12:55pm
Hello all,
With a 10inch Barrel, are there any mods I can do to the valve itself?

Cheers

Kris
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kruzaroad View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote kruzaroad Quote  Post ReplyReply Direct Link To This Post Posted: 31 May 2025 at 8:58pm
There will be. I know from 1322 (pump up) that the valve can have a few threads cut off and inside of the valve can loose some metal. I think you can slightly change the angle of where the air leaves the valve so its not a hard turn for it.
You can drill out the port too a small amount.
There will be stuff on site and the web about how to do it.
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Pauly5 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pauly5 Quote  Post ReplyReply Direct Link To This Post Posted: 01 Jun 2025 at 10:09am
Yea, I think that smoothing off the path of the CO2 by taking a dremel to the transfer port will help a bit, but don't think there's a huge gain in power, still an increase is an increase.

Kruz, cutting the threads and boring out the valve works well for the pumper because it increases the volume of the plenum, or the stored air for each shot. With the 2240 its a direct path from the capsule to the poppet valve.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Microbugs Quote  Post ReplyReply Direct Link To This Post Posted: 01 Jun 2025 at 2:37pm
Yes, port the valve, remove the right angle that feeds into the vavle into the connection to the barrel. You can also thin down the valve stem to allow better gas flow out of the valve, but don't go too far or the stem with break after a while (been there).
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Kris View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kris Quote  Post ReplyReply Direct Link To This Post Posted: 05 Jun 2025 at 1:37pm
Thanks


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Kris View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kris Quote  Post ReplyReply Direct Link To This Post Posted: 05 Jun 2025 at 1:38pm
Makes sense

Thanks

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kruzaroad View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote kruzaroad Quote  Post ReplyReply Direct Link To This Post Posted: 13 hours 46 minutes ago at 3:14pm
So i been looking at 2240 valve on line out of curiosity,
It would seem you can buy a better flow valve from boss. A better transfer port to barrel, up to 25% increase in volume flow claimed. Also a stronger hammer spring to keep valve open longer or weaker valve return spring.
Seems the longer barrel is the number one thing to do.
Im assuming as co2 will only pressurize to a certain pressure (not taking heat and cooling affect into account) that goal would be to get enough co2 into the barrel to keep it expanding for the duration of the pellets travel along the barrel.
Thus there will only be so much that can be achieved in actual power gain and that max power is created by having a long continuous push that doesn't stop till after the pellet leaves the barrel. Not a get the pellet going and let momentum carry it the final part of barrel, or a weaker push as the co2 slows its expansion due to decreasing expansion pressure.
Only issue i see would be the gas flow around the pallet as it left the barrel. Your crown would want to be in good nick to encourage even distribution of escaping gas so as not to upset the pellet.
It would also seem you can actually take some metal out of the head of the valve to help volume.
Also the thinning of the valve stem as mentioned above.
Nut as i say, this is from web research.
Hopefully the ppl on here who pull these co2 pistols apart can verify this

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Pauly5 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pauly5 Quote  Post ReplyReply Direct Link To This Post Posted: 13 hours 39 minutes ago at 3:21pm
I will agree with the longer barrel and from experience heavier pellets.

Mintie is a CO2 wizard.
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kruzaroad View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote kruzaroad Quote  Post ReplyReply Direct Link To This Post Posted: 13 hours 32 minutes ago at 3:28pm
If you want to the math for the volume of your barrel here's a blurb on expansion rate
The liquid-to-gas expansion ratio for CO2 is approximately 535:1. This means that for every unit of liquid CO2, it expands into 535 units of gaseous CO2 when vaporized at room temperature and normal atmospheric pressure.

Heres a pipe volume calculator which you can get an approximate volume off. Due to rifling its not going to be exact but should get you in the ball park. It will take mm and inches at the same time so you can do the pellet in mm and barrel in inches
https://www.servicetitan.com/tools/pipe-volume-calculator



Edited by kruzaroad - 13 hours 16 minutes ago at 3:44pm
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Kris View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Kris Quote  Post ReplyReply Direct Link To This Post Posted: 5 hours 39 minutes ago at 11:21pm
Thanks, there's plenty to think about.
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