Author Topic: De-gassing issues  (Read 545 times)


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De-gassing issues
« on: June 07, 2018, 11:00:12 AM »
The level of PCP airgun expertise here varies from none to well educated. They're really not difficult to work on if you have the tools. I do, and that's a good thing too!

I've put over 10,000 pellets through my Cobra. I've never cleaned it, and won't as long as it holds the groups. However, I have had to replace several O-rings (wrong ones installed in the first place). I replaced the composite hammer too, as it kept wobbling down the tube, instead of sliding like it should, graphic lubrication notwithstanding! As a result, the Cobra has been de-gassed about six times over the last few weeks.

When you do de-gas a PCP airgun, things don't always seal (perfectly) back up as they should during refill. Valves are notorious for this issue, as are regulators. I've learned then, to fire the gun several times over during the refill process. This tends to help the valve seats to reseal as it should.

O-rings can leak too, if they aren't properly seated. Coating them with silicon grease is therefore a requirement. Even then it takes them a bit of time for them to reseal, during which they leak a bit. This is one reason why it is so difficult to refill a PCP with a hand pump after de-gassing.

Experts know of these scenarios, neophytes, not so much. But now you do.

  • Roswell, New Mexico

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.