Gas problem with FWB C25

periodthree · Post by **periodthree** » Sun Feb 26, 2012 12:03 am

Hi there,

I'm a new shooter and have recently purchased a Feinwerkbau C25 as my first AP. My scores have leapt and have continued to improve steadily each time I have used. I guess this means based upon my standard of competence, the pistol suits me.

Yesterday I competed in my first competition. I thought I had prepared properly in that I had filled a few days earlier both CO2 cylinders. Both were chilled before filling and were half and 3/4s full on the basis of their weight.

During the competition it appeared I emptied both of them and crucially I "thought" I ran out of gas and did not complete the match. I could see the pistol spinning the pellets during flight just before it stopped firing.

I weighed both cylinders when I got home and both were about half full.

I'm perplexed. Do I have a problems with my seals? The temperature was quite warm (probably around 30 - 35 degrees C) so was the temperature mucking around with gas pressure?

Any advice would be greatly appreciated.

PaulB · Post by **PaulB** » Sun Feb 26, 2012 12:57 am

I have previous experience with valves not opening and the CO2 gun appearing empty with temperatures of about 32 C. We had to have the shooters rest their guns on ice bags between shots to keep them working.

Silvershooter · Post by **Silvershooter** » Sun Feb 26, 2012 8:20 am

That's interesting, I have a couple of FWB C25s, but I don't anticipate this problem in England.

Rover · Post by **Rover** » Sun Feb 26, 2012 10:01 am

High temperatures CAN be a problem with CO2 guns. It's the reason I sold mine.

I live in the SW desert where temps often reach over 46C (115F). The CO2 pressure builds until it restricts or locks up the regulator.

I shot one match where I had to stop shooting and bleed the cylinder to cool it before continuing (several times). Fortunately, we now have greatly improved air conditioning in the range.

So there is your "quick fix", but you could trade off for a SSP such as the Pardini K58 or spend a lot more for a PCP, which I did because I found one at an extremely low price.

I've also heard of shooters cooling the cylinder by resting the gun on a bag of ice once in a while. I think that might be the best idea.

periodthree · Post by **periodthree** » Sun Feb 26, 2012 6:14 pm

Thanks for all the information.

I'll try using a ice mat for the next few matches and see how that goes. It sounds like CO2 and the Australian summer don't agree with each.

periodthree · Post by **periodthree** » Mon May 21, 2012 2:39 am

Problem solved. I bought a new seal kit and had it installed and the pistol is now working beautifully.

A good outcome though I will keep the CO2 cylinder cool in the dead of summer.

For those interested, there is a dude from Germany selling seal kits for older FWBs on eBay. Cost me 40 Euros.

luftskytter · Post by **luftskytter** » Mon May 21, 2012 3:29 pm

Just one thing: 1/2 or 2/3 is not "full".
Many shoot FWB CO2 in my club.
They mostly fill to within 10 grams or less from FWBs recommende max.
It's all stamped on the bottle, and we use a digital kitchen scale with one gram accuracy.

And yes, we leave the cylinders in the freezer for about 10 minutes. sometimes we forget them there for a while ;-)
If you get to much CO2 you should bleed off a little.

Shooting actually cools a CO2 system down.......