sopel
Horse Wrangler
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Post by sopel on Feb 27, 2024 15:27:05 GMT
Dear forum members, I seek your wisdom, help and guidance.
Last week, happily working on tightening my groupings at a local range, I tried inserting a new CO2 capsule (3rd of the day) when all of the sudden all of the gas was released immediately, as if the tip of the capsule did not make a proper seal. I have now tried 3 more capsules with the same effect, no matter how quickly I try to tighten them.
What happened, what am I doing wrong? It all worked perfectly fine, until it just didn't. No warning signs, no slow leaks, just bang and gone... The only thing that comes to mind is that it coincided with starting a new batch of capsules, that look slightly different to the previously used (both Umarex though) - there is a small groove on the neck of the canister, where the previous ones were smooth all the way - but I am not sure if that would have an impact? The pistol used is a Umarex H&K USP blowback. Any help will be appreciated...
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Post by flatrajectory on Feb 27, 2024 17:05:09 GMT
Take a photo of the neck of the offending capsule and post it on here.
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Post by scanny on Feb 27, 2024 17:36:15 GMT
I would start to test it with different brand of CO2 capsule, and after that with different magazine. Or if you have only one magazine I would take it apart and look at the seals.
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talyllyn
The Sheriff of Dodge
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Post by talyllyn on Feb 27, 2024 21:14:56 GMT
Does the seal still look sound?
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twodoctors
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Post by twodoctors on Feb 28, 2024 6:37:02 GMT
Grease the firing/CO2 triggering mechanism on the mag. ie the bit where the hammer hit the actuator. It might be slightly stuck. Had similar problem before on a used gun I bought and that fixed it.
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Post by HeadHunter on Feb 28, 2024 7:55:03 GMT
Sounds like the seal has gone to me, sometimes overtightening the CO2 screw can cause the seal to be squished too much that it doesn't bounce back to it's original shape, a good remedy for this is to soak the seal in pellgun oil and leave it overnight (try keeping the mag upside down so that the oil can permeate the seal properly), I've found that that works in the majority of cases, especially on mags that haven't been used regularly or in a good while (as they can dry out and lose their spongyness).
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sopel
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Post by sopel on Feb 28, 2024 13:12:13 GMT
Does the seal still look sound? Problem is, I don't really know what 'sound' looks like... Tis my first venture into the world of airguns...  Can't see it broken, appears smooth and even... |
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sopel
Horse Wrangler
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Post by sopel on Feb 28, 2024 13:14:54 GMT
Sounds like the seal has gone to me, sometimes overtightening the CO2 screw can cause the seal to be squished too much that it doesn't bounce back to it's original shape, a good remedy for this is to soak the seal in pellgun oil and leave it overnight (try keeping the mag upside down so that the oil can permeate the seal properly), I've found that that works in the majority of cases, especially on mags that haven't been used regularly or in a good while (as they can dry out and lose their spongyness). Soaking, will check again tomorrow. Is it possible for the seal to just give in like that from one capsule to another? I would have though a leak would be more expected, a slow 'psssst', rather than a 'bang' and a frosty mag in my hand... |
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sopel
Horse Wrangler
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Post by sopel on Feb 28, 2024 13:21:27 GMT
Grease the firing/CO2 triggering mechanism on the mag. ie the bit where the hammer hit the actuator. It might be slightly stuck. Had similar problem before on a used gun I bought and that fixed it. Thanks! I don't think that's it, as the gas appears to be escaping down through the tightening nut, greased anyway...  |
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sopel
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Post by sopel on Mar 4, 2024 12:10:48 GMT
OK, and so the saga continues. Soaking in pellgunoil did not help. I managed to find a couple of capsules from the original batch, unfortunately got the same result (i.e. explosive discharge of the CO2 when trying to tighten), so that turned out to be a red herring as well. I guess HeadHunter was right and the seal is gone (bought the gun second hand, no idea how long it sat in the shop, but the seal was bone dry when I got it). Having manufactured the 'special removal tool' out of a straight mending plate, which happened to be just the right width and thickness, and having figured out the seal unit was left threaded, I took out the entire assembly for inspection. Indeed the seal seems squashed, and hard as nail, so it probably needs replacing. Here's the zing. I managed to find a replacement assembly: But not only it's not available, but it seems somewhat excessive to replace the entire assembly, for one small seal. So here's my question to the wiser and more experienced community members (i.e. pretty much everyone else but me) - is it possible to buy just the seal, and if yes, where? All resources I found refer to specific gun makes and models, rather than the size of the seal, so it's a bit tricky to find a replacement... The seal dimensions are - outer diameter app. 8.3mm, inner diameter 3.5mm, thickness (current) 1.6mm, though I suspect it would be more like 2mm when new. Again, any help and guidance will be greatly appreciated.
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Post by HeadHunter on Mar 4, 2024 19:21:37 GMT
OK, and so the saga continues. Soaking in pellgunoil did not help. I managed to find a couple of capsules from the original batch, unfortunately got the same result (i.e. explosive discharge of the CO2 when trying to tighten), so that turned out to be a red herring as well. I guess HeadHunter was right and the seal is gone (bought the gun second hand, no idea how long it sat in the shop, but the seal was bone dry when I got it). Having manufactured the 'special removal tool' out of a straight mending plate, which happened to be just the right width and thickness, and having figured out the seal unit was left threaded, I took out the entire assembly for inspection. Indeed the seal seems squashed, and hard as nail, so it probably needs replacing. Here's the zing. I managed to find a replacement assembly: But not only it's not available, but it seems somewhat excessive to replace the entire assembly, for one small seal. So here's my question to the wiser and more experienced community members (i.e. pretty much everyone else but me) - is it possible to buy just the seal, and if yes, where? All resources I found refer to specific gun makes and models, rather than the size of the seal, so it's a bit tricky to find a replacement... The seal dimensions are - outer diameter app. 8.3mm, inner diameter 3.5mm, thickness (current) 1.6mm, though I suspect it would be more like 2mm when new. Again, any help and guidance will be greatly appreciated.
I think these are the ones you want buddy..... www.ebay.co.uk/itm/204071090603?£6.96 for two including post |
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sopel
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Post by sopel on Mar 11, 2024 12:57:21 GMT
Thanks a bunch to everyone who replied, and especially to @headhunter for the link. If it wasn't for this, I would probably be cutting little rings out of old inner tubes. :-) All is working now, good as new! :-)
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Post by HeadHunter on Mar 12, 2024 7:56:48 GMT
Thanks a bunch to everyone who replied, and especially to @headhunter for the link. If it wasn't for this, I would probably be cutting little rings out of old inner tubes. :-) All is working now, good as new! :-)
That's great news buddy  |
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Can't see it broken, appears smooth and even...
