Filling of PCP tank

Bob Stewart · Post by **Bob Stewart** » Thu Dec 23, 2010 2:05 pm

Hi everyone,

I recently purchased a FWB 700 and a hand pump. In the manual it states that hand pumps are not recommended with no further reasoning as to why. Can anyone tell me why.

Thanks,
Bob

Richard H · Post by **Richard H** » Thu Dec 23, 2010 2:43 pm

The only down side of a pump is possible condensation. I would figure with rifle tanks its more of a problem due to the size. If pumping, fill it slow don't let it get too hot and use what ever condensate management system you have.

Guest · Post by **Guest** » Thu Dec 23, 2010 3:03 pm

Richard H wrote:The only down side of a pump is possible condensation. I would figure with rifle tanks its more of a problem due to the size. If pumping, fill it slow don't let it get too hot and use what ever condensate management system you have.

You can only do about 20 strokes before you have to stop to let it cool down. It took about 200 strokes to fill the my cylinders so you can get plenty of exercise. If you don't stop you can risk generating heat and then moisture. If you generate to much heat you can effect the seals and at the same time condensate. I had a hand pump before they came out with ones you can drain and the moisture had rusted the metal inside to the point it seized up. You can imagine if it's generating that kind moisture what your pump will putting into your rifle cylinder.

Maybe the new ones that have a filter and drain can do better, but even the electric compressors have several sets of filters to keep the moisture out of the air.

Richard H · Post by **Richard H** » Thu Dec 23, 2010 3:43 pm

The damage is actually in the cylinder, the small amounts of moisture that would get in to the pistol/rifle are really not that big a deal would quickly dissipate. The moisture that is stuck and sits in the cylinder can cause pitting in the cylinder, which could weaken it.

Bob Stewart · Post by **Bob Stewart** » Thu Dec 23, 2010 10:47 pm

So it's all about moisture. Got it.
My pump has a moisture filter after the particle filter in the handle, but it seems as though they should have the moisture filter at the end of the hose before it goes into the guns air reservoir.

Thanks,
Bob

Richard H · Post by **Richard H** » Thu Dec 23, 2010 11:48 pm

Just don't pump it like a bicycle tire, nice even slow strokes and do it in a few stages. The only real tough one will be the first fill from empty, after that just top it off after each session.

Fortitudo Dei · Post by **Fortitudo Dei** » Sat Dec 25, 2010 4:38 am

A gunsmith I once met from Australia said he could tell almost instantly when servicing AP's & AR's which had been filled from tanks and which from high-pressure hand pumps.
Air from dive shops and BA filling stations goes through a series of high quality moisture traps to reduce humidity to a bare minimum (something which is very necessary with steel SCUBA and BA tanks). The moisture traps installed in various hand-pumps don't come close to professional fill-stations in terms of their ability to remove moisture from the air.
The ambient relative humidity can also have a big impact on the level of risk the use of a hand pump imposes on your AP / AR (i.e. using a hand pump in Arizona in winter is far less risky than using one in Florida in summer).

Hemmers · Post by **Hemmers** » Sun Jan 02, 2011 2:56 pm

Yeah, as others have said.

(1) It's a lot of effort
(2) Breathing air from dive shops is filtered and dried, reducing possible condensation build-up in your tank and valves/trigger mechanism.

kevinweiho · Post by **kevinweiho** » Mon Jan 03, 2011 1:46 am

Fortitudo Dei wrote:A gunsmith I once met from Australia said he could tell almost instantly when servicing AP's & AR's which had been filled from tanks and which from high-pressure hand pumps.
Air from dive shops and BA filling stations goes through a series of high quality moisture traps to reduce humidity to a bare minimum (something which is very necessary with steel SCUBA and BA tanks). The moisture traps installed in various hand-pumps don't come close to professional fill-stations in terms of their ability to remove moisture from the air.
The ambient relative humidity can also have a big impact on the level of risk the use of a hand pump imposes on your AP / AR (i.e. using a hand pump in Arizona in winter is far less risky than using one in Florida in summer).

I live in Puerto Limón, Costa Rica (which is at sea level.)

If I use a dehumidifier in a small room along with my FX pump, will this combination considerably reduce the moisture being pumped into my PCP's?

Richard H · Post by **Richard H** » Mon Jan 03, 2011 10:54 am

It would conceivably reduce it to what ever you reduce the humidity level to in the room, still no where near dry as that provided in a dive shop. I would think living on the coast in Costa Rica dive shops would be plentiful.

kevinweiho · Post by **kevinweiho** » Tue Jan 04, 2011 11:51 am

Richard H wrote:It would conceivably reduce it to what ever you reduce the humidity level to in the room, still no where near dry as that provided in a dive shop. I would think living on the coast in Costa Rica dive shops would be plentiful.

Scuba diving is not common in the area where i live in, and people usually go to the beach to take a dip or swim... So, i guess i'll continue using the dehumidifier and add a filter/dessicant to the FX pump.

TerryKuz · Post by **TerryKuz** » Tue Jan 04, 2011 6:30 pm

There are two types of tanks, scuba, and SCBA. SCBA is the airpac firemen use. These get filled to a nominal 4500psi as compared to 3000psi for the scuba tank. So SCBA equipment and fill level is preferable. Anyway, I have a 88 cu ft scba, and I get 35 fills for 300 shots, so a fill is a ton of shooting. I get mine filled at Penn State, and many fire companies fill tanks for a small donation. Give the cost of 22 rimfire compared to pellets, tanks and filling is cheap. Here is a link to fill stations/

http://www.network54.com/Forum/79537/me ... ookmark+it