N/A Moisture in PCP airguns

Just a friendly warning. I know we are talking moisture but don't fill a Scuba tank with a Yong Heng type compressor and use it as breathable air. Many decades ago to have a compressor you had to spend some bucks. Reason was not many made and fresh air requirements. Anyway I bought a Nardi Atlantic in about 1998. It is a fresh air compressor rated at 4500 psi. Oil for these are very expensive and they tell me if I use regular synthetic compressor oil it can no longer be used for fresh air. I currently use a Yong Heng and one of the gold Chinese moisture filters. I have not heard of any of their filters, tanks ,or guns exploding. I will say I have not always found all the screws tight.

AI have a question since we seem to have a concern about corrosion. Has anyone had to replace or had a failure due to corrosion specifically from moisture in their air. I'm relatively new to this (mid 90's) and only have 6 PCP's so my experience is limited. How big a problem is this.

Almost forgot. I recently purchased an expired CF tank 45 min. It came with a valve with a tube that extended down in the tank like the photo above thread.
 
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is that a lake dive?
No, ;), I am in the Red Sea there. In the water anything at a distance turns bluish green on a camera sensor. Water absorbs reds in the first ten to twenty feet and even powerful strobes like on my camera system are only good for about 6 feet maximum (12 feet to and from:) ). The brain is much more than a simple sensor and since it knows something is red it may appear red even when little red spectrum is left. We see what we want to see.

Our PCP compressors, though some show them being used for scuba tanks, are not suitable for breathing air. Breathable air must be free of oils and CO. Nothing goes in my scuba tanks, even the ones used for boosting rifles or scba bottles dedicated to PCP, but pure filtered air from a scuba fill station.

I have not seen any moisture in my PCP scba tanks. I do get water in the centrifugal gold filter. But past there, nothing.
 
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I ordered a 6.8L tank from Amazon, still waiting for it but the valve doesn't have any extended tubing or stem, looks like i could just turn it upside down to purge any water collected in there if necessary, have the CS4 coming at the same time to fill this thing.

My thought process was that the tank will be used as a main moisture collector and heat-dump reservoir, once the tank is completely cooled down, the air being pumped into PCP gun from the tank will be dry and cool, it should theoretically contains less moisture once the water settled at the bottom of the tank, and having an inline moisture collector wouldn't be as big of a deal or even necessary since the tank will be collecting moisture instead, one less thing to maintain. Another reason for getting the tank is so i can bring it to the range instead of compressor.


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You don’t want water getting in your tank, as it can lead to corrosion of the aluminum liner. Things don’t behave the same in there with 200-300 bar of air along with the water.

The dip tubes are there in SCBA valves and SCUBA tanks as a life saving measure to act ad a fail safe in case water were to get in the tanks. But the goal is to keep the water out at all times.

While it is not a bad idea to occasionally invert your tank and purge it “just in case” (since it won’t hurt anything), you should not plan on having water condense in there as you likely won’t vent it all out anyways.

Invest in appropriate desiccant drier and your expensive equipment will last much longer. It is part of the equipment we need in tii go s hobby.
 
TUXING PCP Oil Water Filter High Pressure Diving Separator Air Compressor Scuba
ebay under gold desicant filter pcp
Always been curious if filling my gun to 250 bar thru one of these increases load and fill times on my GX C3 and is it significant?
 
Always been curious if filling my gun to 250 bar thru one of these increases load and fill times on my GX C3 and is it significant?
I'm sure it would increase the fill time by minutes? exactly how long I honestly couldn't say. When I was using them I had a Yong Heng, I had/have a very large C/F bottle (109cu/ft) and would top it off. With the filter it took a couple minutes to pressurize to 225bar before I would open the bottle valve and begin filling it which then take another 30 minutes +/_ to pressure up to 250-260 bar.
 
Just a friendly warning. I know we are talking moisture but don't fill a Scuba tank with a Yong Heng type compressor and use it as breathable air. Many decades ago to have a compressor you had to spend some bucks. Reason was not many made and fresh air requirements. Anyway I bought a Nardi Atlantic in about 1998. It is a fresh air compressor rated at 4500 psi. Oil for these are very expensive and they tell me if I use regular synthetic compressor oil it can no longer be used for fresh air. I currently use a Yong Heng and one of the gold Chinese moisture filters. I have not heard of any of their filters, tanks ,or guns exploding. I will say I have not always found all the screws tight.

AI have a question since we seem to have a concern about corrosion. Has anyone had to replace or had a failure due to corrosion specifically from moisture in their air. I'm relatively new to this (mid 90's) and only have 6 PCP's so my experience is limited. How big a problem is this.

Almost forgot. I recently purchased an expired CF tank 45 min. It came with a valve with a tube that extended down in the tank like the photo above thread.
That’s what I was thinking Jim, how big of a problem is this ? Because I bet most don’t take as many precautions as even we do.

If this was a problem I’m sure we’d hear about it en masse.
 
Just to play it safe I've ordered exactly that from Amazon, the gold tube from Tuxing, plus 7lb of 3A Molecular Sieve, can those media be dry out and reuse/recharge?
if I remember corectly you can put them on a cookie sheet in the oven on low for 15-20 minutes, might want to look that up.
 
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if I remember corectly you can put them on a cookie sheet in the oven on low for 15-20 minutes, might want to look that up.
I have a few laptop coolers that I could put to good use, i was thinking to just place the moist Molecular Sieve on paper towel on top of the laptop cooler to dry them out, it's how i dried the pellets and slugs that I had to wash as well....haha.

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After weighing the options and buying multiple guns I purchased an Alkin w31 mariner and haven't looked back.

I'm sure the Alkin W31 is great, that's some professional compressor right there.... but it's too expensive lol it would be worth it if you shoot alot, or have a lot of PCP guns(or some big bore beast)😁
 
After 2hr, i stopped the CS4 for it to cool down, pulled the inline filter and there's very little moisture in it, one of the foam insert was moist but not soaking wet or anything, and the 2nd foam filter is bone dry, the CS4 seems to have excellent moisture control, i think the gigantic gold filter with Molecular Sieve is going to be super sufficient, maybe even a bit overkill. Grease pot is fine and seems to be working as intended, no damage restrictor/gasket like i saw some people reported on theirs, it's so much quieter than my CS3 and the other shoebox compressor.

i ran the CS4 and tank in a separate room in a climate controlled basement, <50% RH at the basement at 70F degree year round. I'm trying to stay away from the setup while it's running.....a bit paranoid and don't want to stay too close to high pressure equipment. I went to check on it every 30min to make sure no air leak from anywhere, and to crack open the bleeder valve on the CS4 while it's pumping to release whatever moisture built up in there.

I set the CS4 first limiter to 280 bar and 2nd limiter to 300 bar, no need to push the fill to the absolute max at 300 bar even though the tank is rated for it, and the CS4 is rated at 400 bar.

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Or, you can get the 6k PSI dry nitrogen delivered and not worry about any of this bs.
How much does it usually cost?

I was contemplating on letting our local dive shop fill it for like $10 lol Now that the M4 honeymoon is over, i don't plow through the same amount of pellets like i used to (at one point it was 300~400 rounds per day), the 6.8L tank will last me at least 2 weeks worth of refills now, so $20 a month is very manageable.

The CS4 just done filling the 6.8L tank, about 4hr from 0 to 280 bar with a break in between, so it ain't too bad. i figured i only need to run the CS4 twice and no more than three times a month now, it's so quiet and does a great job in moisture management so far, only one out of two foam insert from the inline filter got a bit moist so it's pumping out relatively dry air into the tank.
 
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How much does it usually cost?

I was contemplating on letting our local dive shop fill it for like $10 lol Now that the M4 honeymoon is over, i don't plow through the same amount of pellets like i used to (at one point it was 300~400 rounds per day), the 6.8L tank will last me at least 2 weeks worth of refills now, so $20 a month is very manageable.

The CS4 just done filling the 6.8L tank, about 4hr from 0 to 280 bar with a break in between, so it ain't too bad. i figured i only need to run the CS4 twice and no more than three times a month now, it's so quiet and does a great job in moisture management so far, only one out of two foam insert from the inline filter got a bit moist so it's pumping out relatively dry air into the tank.
Most dive shops wont fill above 2800-3200 psi- mayby a paintball shop.
 
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Also, this helps to illustrate why hand pumps – used properly – work so well. If we pump slowly, the air charge cools in the base of the pump before going into the gun. Add in frequent cool-down breaks for the pump – no more than about 50 pump strokes or so, then venting the line and letting it cool for 10-15 minutes – and the air charge stays cool enough that there really is nothing to condense out. Maybe a tiny amount, but it will likely flash to vapor again as the pressure in the gun drops (since lower pressure air can hold a bit more vapor). Done right, handpumping won’t lead to condensed water in guns, even in Hawaii😉.

Happy shooting (and pumping)!
Thanks for pointing this out, as it has always been the primary reason I've remained a dedicated hand pump user. I am also slow when it comes to shooting, so refilling slowly fits my style (and my budget). Pump slow and purge often. In 10 years, I've not had any moisture issues in my guns (as evidenced by visual inspections of the reservoirs during preventative maintenance or repairs).
 
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Most dive shops wont fill above 2800-3200 psi- mayby a paintball shop.
oh wow i didn't know that. lol

The CS4 is incredibly quiet and effective in keeping moisture under control, the built in water cooling system from CS4 is awesome too! I almost went with the Yong Heng that everyone recommended on Reddits. So glad I got the CS4 instead, don't have to use ghetto rig with tubings hanging everywhere to run pump off of bucket of water, no oil change needed either, the grease cup only needed 1 full turn every 4 to 6hr of runtime, from what I read, it has about 9 turns total, when it ran out it should only take few seconds to refill, I bought 4oz of recommended grease for $16 from Amazon, it would last for a few years, love both the new tank and CS4 so far.
 
How much does it usually cost?

I was contemplating on letting our local dive shop fill it for like $10 lol Now that the M4 honeymoon is over, i don't plow through the same amount of pellets like i used to (at one point it was 300~400 rounds per day), the 6.8L tank will last me at least 2 weeks worth of refills now, so $20 a month is very manageable.

The CS4 just done filling the 6.8L tank, about 4hr from 0 to 280 bar with a break in between, so it ain't too bad. i figured i only need to run the CS4 twice and no more than three times a month now, it's so quiet and does a great job in moisture management so far, only one out of two foam insert from the inline filter got a bit moist so it's pumping out relatively dry air into the tank.
I get these:


It sits in my garage and I fill a smaller CF tank that then fills my AGs. Around $200 every time they exchange the cylinder, which is twice per year. Considering that I was buying a new compressor every couple years, it’s not a substantial increase in cost and I certainly don’t miss the chugging noises and slow fill. The downside is that you have to buy the high pressure CGA regulator (around $700) but I’ve been doing it this way for six years, so the cost spreads out. Also, with pure dry nitrogen, you get a little power boost, mostly due to the absence of water in the charge, although pure nitrogen is also lighter than nitrogen mixed with oxygen (air), so less energy is robbed accelerating the gas. That’s getting a bit nerdy so let’s just say that the absence of water and speed of use are worth it to me.
 
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How many pcp owners go to all this extreme to keep Moisture out ?

I stress over it and use the large gold filter and an inline “ cigarette “ filter.

I’ll bet many, many pcp owners don’t give to much more thought to this. So I’ll ask again …. Have there been any incidents of heavy moisture in the airguns tank that caused a failure of any sort ??
 
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