I recently bought a FX Impact M3 and have been experiencing what I call sweating around the rear of the barrel and onto the plenum. I was told by the dealer and FX that it may be humidity, warm weather causing it. I am not seeing any reg creep or fill pressure loss? Has anyone else experienced this?
FX Impact M3 sweating
- Thread starter jsbill55
- Start date
What's your air fill source?
What were the weather conditions when that pic was taken? I've never had mine sweat there even in summer months...and we see hot and humid during the summer.
What were the weather conditions when that pic was taken? I've never had mine sweat there even in summer months...and we see hot and humid during the summer.
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I was going to say it's the plenum cooling with the pressure drop after every shot and causing the condensation on the rear of the plenum when it cools below the dew point in a humid environment, but the patch of condensation on the upper frame hints that it's possibly an air leak from the breech area.
Drape a small piece of light tissue paper or toilet paper over the cheek rest and breech area where the condensation is happening and take a shot and see if there's an air leak. Make sure you're firing a pellet so there's plenty of pressure in the barrel. If the paper jumps, there's a leak.
It's possibly a transfer port or breech liner lock o ring leak that's leaking air near the rear of the plenum on every shot, and that blast of rapidly expanding and cooling air is what is causing the condensation. Hopefully it's not any o rings in the valve or rear block, that's a more involved repair.
Drape a small piece of light tissue paper or toilet paper over the cheek rest and breech area where the condensation is happening and take a shot and see if there's an air leak. Make sure you're firing a pellet so there's plenty of pressure in the barrel. If the paper jumps, there's a leak.
It's possibly a transfer port or breech liner lock o ring leak that's leaking air near the rear of the plenum on every shot, and that blast of rapidly expanding and cooling air is what is causing the condensation. Hopefully it's not any o rings in the valve or rear block, that's a more involved repair.
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Thanks for the responses guys... I'll try the paper to see if there is a leak upon firing. I now have had the opportunity to shoot in 75 degree weather and 45 degree weather. It condensates in both conditions. By the way, if there is a leak, shouldn't it be covered under warranty? I bought the rifle last month...
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I’m in South Texas. In the morning, sometimes it’s very humid. Mine will do the same thing. Mine will also get some condensation at the moderator. So, it’s not a leak, just bad humidity. When I shoot it later in the day when the fog, humidity has burned off, it does not do this anymore.
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There is a pressure / temperature relationship going on. When high pressure goes to low pressure it gives up heat. When temperature reaches dew point water forms on surface. Like a glass of ice tea on a hot summer day. That is basic thermo dynamics. MM
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Hi JSBill55,
If you have any concerns please feel free to contact our customer service or technician department.
Regards,
FX Airguns USA
Contact
Monday - Thursday 9 AM - 4 PM EST
Fridays 9 AM - 3 PM EST
Phone: +1 866 639 0772
[email protected]
If you have any concerns please feel free to contact our customer service or technician department.
Regards,
FX Airguns USA
Contact
Monday - Thursday 9 AM - 4 PM EST
Fridays 9 AM - 3 PM EST
Phone: +1 866 639 0772
[email protected]
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Like I mentioned earlier, it could just be condensation forming because the plenum and breech area are cooling below the dew point from the air expanding in the transfer port and barrel on every shot, or it might be an air leak after the valve seat near the breech area. The simple tissue paper test will let you know.
If the tissue paper test shows there's no air leak from the breech area on each shot then there's nothing wrong with the rifle-- it's just condensation forming on the parts of the rifle that are at or below the dew point for the current conditions. The more shots you take in quick succession, the cooler those areas will get.
It's just somewhat odd to me that your picture shows condensation on the outer barrel shroud and the upper frame, which is why I suggested checking for an air leak near the breech. Hopefully there aren't any leaks.
Report back with what you find!
If the tissue paper test shows there's no air leak from the breech area on each shot then there's nothing wrong with the rifle-- it's just condensation forming on the parts of the rifle that are at or below the dew point for the current conditions. The more shots you take in quick succession, the cooler those areas will get.
It's just somewhat odd to me that your picture shows condensation on the outer barrel shroud and the upper frame, which is why I suggested checking for an air leak near the breech. Hopefully there aren't any leaks.
Report back with what you find!
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My MK2PP sweating was well, last week at my range, windy, raining, windy and raining again, about 9C, and I shot about 200-250 rounds, I noticed this when finished and started packing. First thought that is a condensation from my nose 
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Condensation from your nose for sure!
Had the same thing hapen with my WC MK3...
Please confirm jsbill55?
Had the same thing hapen with my WC MK3...
Please confirm jsbill55?
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After seeing all of the great responses I am thinking it may be the reaction of hot - cold air and since I'm left handed, maybe from resting my cheek on the cheek rest on the right side of the gun... haven't had a chance yet to see if there may be a leak with the tissue paper test yet. I'll try to do that tonight.
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Hi All,
I just got in from trying to zero my M3 at 75 yards and observed sweat on the plenum and icing on the barrel and moderator. Temp: 39F, Dew point: 39, Humidity: 97%, overcast and light fog.
I'm not confused or surprised by the moisture/frost however has anyone experienced inconsistent accuracy as a result of this? Thanks
I just got in from trying to zero my M3 at 75 yards and observed sweat on the plenum and icing on the barrel and moderator. Temp: 39F, Dew point: 39, Humidity: 97%, overcast and light fog.
I'm not confused or surprised by the moisture/frost however has anyone experienced inconsistent accuracy as a result of this? Thanks
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Hi Bill,The " very high pressure " air passing into the plenum gets heated. I've heard of this. If you shoot to fast the air will get really hot. Hot air inside,cool air outside =condensation in NH. Also heard it affects accuracy.That's my thought.
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