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Air tank

Posted: Tue Aug 03, 2021 6:37 am
by conradin
My cylinder seems to run out of air more and more times. This is 200 pressure air cylinder. Now it barely reaches 150.
Is there a sign you have to notice that the air tank is about to get refill soon?

Re: Air tank

Posted: Tue Aug 03, 2021 12:39 pm
by marky-d
I'm not sure I'm understanding your question, but if you are saying that you refill your air gun cylinder with something like a SCUBA tank, and you are only getting to 150 bar instead of 200 bar, then yes, you will need to refill your SCUBA tank if you want to reach 200 bar again.

When you refill your cylinder from another tank, you cannot achieve a final pressure higher than whatever is in your tank.

marky-d

Re: Air tank

Posted: Tue Aug 03, 2021 1:04 pm
by Rover
Just get rid of that crappy PCP and switch to CO2. It stays at the same pressure and fill level until the last drop of liquid is depleted. It will easily give you twice as many shots for each cylinder fill and a tank will last FAR longer.

Then you can kick back and relax anxiety-free, knowing that your gun is not becoming closer to being useless in an indeterminate manner with every shot. Think of the expensive 'ludes you'll save on.

Re: Air tank

Posted: Tue Aug 03, 2021 6:30 pm
by Leon
To avoid this problem, I actually purchased a 300 bar scuba tank - and have it pumped up to 300 bar by the dive shop.

It's pretty easy to refill the air pistol's cylinder to ONLY 200 bar if you do it slowly - and you then have a huge margin of air before you even reach the 200 bar threshold.

Re: Air tank

Posted: Tue Aug 03, 2021 7:12 pm
by william
Leon wrote: Tue Aug 03, 2021 6:30 pm To avoid this problem, I actually purchased a 300 bar scuba tank - and have it pumped up to 300 bar by the dive shop.

It's pretty easy to refill the air pistol's cylinder to ONLY 200 bar if you do it slowly - and you then have a huge margin of air before you even reach the 200 bar threshold.
There's a familiar word for 200 bar cylinders filled from a 300 bar source without a regulator in between. KA-BOOM! It's the kind of thing you can get right dozens, even hundreds, of times. But get it wrong once....

Re: Air tank

Posted: Tue Aug 03, 2021 9:27 pm
by bandur60
What is the possibility, or drawbacks, of using a 300 BAR tank and regulating it down to 200 BAR between the scuba tank and fill adapter? I've wondered about this for some time. Would it just turn out to be a plumbing nightmare or cost prohibitive? Serious question.....

Re: Air tank

Posted: Tue Aug 03, 2021 9:58 pm
by BobGee
I would expect that the pistol cylinders are proof tested to a minimum of 250bar but I’m not sure how they’d handle inadvertently going to 300bar. I expect that KA-BOOM would be the operative description. At least with an aluminium cylinder it might just split so no shards/shrapnel except perhaps end caps circulating the garage at high velocity.

Bob

Re: Air tank

Posted: Tue Aug 03, 2021 10:02 pm
by BobGee
bandur60 wrote: Tue Aug 03, 2021 9:27 pm What is the possibility, or drawbacks, of using a 300 BAR tank and regulating it down to 200 BAR between the scuba tank and fill adapter? I've wondered about this for some time. Would it just turn out to be a plumbing nightmare or cost prohibitive? Serious question.....
I’m sure it’s possible: regulators are just appropriately sized pistons and springs in a sturdy housing after all. I don’t know anyone who makes them commercially. To get one made would be expensive because of the proof testing and certification that would be required by the maker to cover its arse.

Bob

Re: Air tank

Posted: Thu Aug 05, 2021 6:30 am
by m1963
bandur60 wrote: Tue Aug 03, 2021 9:27 pm What is the possibility, or drawbacks, of using a 300 BAR tank and regulating it down to 200 BAR between the scuba tank and fill adapter? I've wondered about this for some time. Would it just turn out to be a plumbing nightmare or cost prohibitive? Serious question.....
It is being done. Nuvair will make one for you, for about $750. You would need to call them and discuss how it will be used to be sure it is made for your needs.

https://www.nuvair.com/products/fill-pa ... lator.html

Best regards,
m1963

Re: Air tank

Posted: Thu Aug 05, 2021 9:29 pm
by KDZ
Besides a step-down regulator there is another way to use 300 bar supply SCBA tank to safely fill to 200. I have one of these, originally (and still) for filling PCP air rifles:

http://experthpa.com/cart/cart.php?m=pr ... etail&p=58

It has a slow-fill regulator that would be hard to over-fill (but still possible), and you need an adapter for the air pistol fill flange like this:

https://www.pyramydair.com/product/air- ... 58#Reviews

With the valve wide open it takes about 5 min to fill my FWP P44 tank from 100 to 200. So if you watch it is pretty much idiot proof, unless you walk away or get distracted.

Re: Air tank

Posted: Thu Aug 05, 2021 11:06 pm
by Rover
"So if you watch it is pretty much idiot proof, unless you walk away or get distracted."

So you're saying that Conradin won't blow his head off unless he is careless when partaking of his "medicinal herbs."

Re: Air tank

Posted: Fri Aug 06, 2021 1:38 am
by David M
Stay tuned, for the up and coming Darwin Awards coming to a forum near you...

Re: Air tank

Posted: Fri Aug 06, 2021 5:54 am
by conradin
My rifle can only reaches up to 70 shots and then it runs out of air.

Re: Air tank

Posted: Fri Aug 06, 2021 5:59 am
by conradin
Rover wrote: Tue Aug 03, 2021 1:04 pm Just get rid of that crappy PCP and switch to CO2. It stays at the same pressure and fill level until the last drop of liquid is depleted. It will easily give you twice as many shots for each cylinder fill and a tank will last FAR longer.

Then you can kick back and relax anxiety-free, knowing that your gun is not becoming closer to being useless in an indeterminate manner with every shot. Think of the expensive 'ludes you'll save on.
At the club we do use FWB600 and other pneumatic single stroke pump rifle. But there are the same amount of users that use air cylinder. One of them uses a Walther (hence 300 instead of 200). Nobody uses CO2. In fact, I have never met anyone using a CO2 cylinder. In fact, I do not even know how to find CO2 supplier.

Re: Air tank

Posted: Fri Aug 06, 2021 7:26 am
by Rover
Well, Conradin, since I told you where, how, and how easy it is to find CO2, I guess you didn't try very hard. AND since you bought your SCUBA tank from the other side of the country when you live on the Pacific Ocean, I guess there's not much we can do for you.

Re: Air tank

Posted: Fri Aug 06, 2021 2:50 pm
by marky-d
Although I like the idea of the slow-fill, if it takes 5min to fill 100 bar, I think it would be MORE likely to cause me to over-fill...I'd get bored and start thinking about/doing other things. It seems pretty straight-forward to watch a gauge and shut a valve when it hits 200 bar when it only takes a few seconds. I guess I'm living on the edge, but that should be expected when you're into dangerous things like air guns. :)

marky-d

Re: Air tank

Posted: Fri Aug 06, 2021 5:01 pm
by brent375hh
conradin wrote: Fri Aug 06, 2021 5:54 am My rifle can only reaches up to 70 shots and then it runs out of air.
If you only get 70 shots at 200 Bar, could it be that you have your sticker spring over tensioner for high velocity? I would think FWB would have a design that could accommodate for a whole match plus sighted with air to spare.
Have you chrono tested it?

Re: Air tank

Posted: Sat Aug 07, 2021 2:21 am
by conradin
Rover wrote: Fri Aug 06, 2021 7:26 am Well, Conradin, since I told you where, how, and how easy it is to find CO2, I guess you didn't try very hard. AND since you bought your SCUBA tank from the other side of the country when you live on the Pacific Ocean, I guess there's not much we can do for you.
You do realize that all three of my air guns are PCP, so getting a CO2 means getting new rifles and gun. Long time ago I did have a LP1, and that was possible to convert from Co2 to Air. Also, no club that I know of in Nothern California uses CO2. Everyone uses a scuba tank.

Re: Air tank

Posted: Sat Aug 07, 2021 2:29 am
by conradin
brent375hh wrote: Fri Aug 06, 2021 5:01 pm
conradin wrote: Fri Aug 06, 2021 5:54 am My rifle can only reaches up to 70 shots and then it runs out of air.
If you only get 70 shots at 200 Bar, could it be that you have your sticker spring over tensioner for high velocity? I would think FWB would have a design that could accommodate for a whole match plus sighted with air to spare.
Have you chrono tested it?
For my FWB, Buck from Pilguns has done some work on it just to make sure everything is functioning. Also he has chrono tested it He as recorded his chrono test data. But for the Steyr, that is the one that can barely made it to 70 shots. The cylinder of the FWB can only reach is 150 bar out of 200, but the Steyr is hovering between 130 to 140 out of 200. The scuba tank seems to be around 150. I did not check my Haemmerli pistol, since I seldom if ever use it because my hands shake. I use an off hand stand to shoot standing (yes, I am old, plus shaking does not helpguys., Gehmann or Mec should put me on the senior shooting ads in their catalog, although I do not look as good as those models. ), but on kneeling, sitting, and prone I use my sling.

Re: Air tank

Posted: Sat Aug 07, 2021 2:32 am
by conradin
Apparently Scuba shops are very familiar with air gun. Mostly airsoft. One of them told me to come back in a couple of days, because he wanted to have a slow fill (thus, 3 days). It did make a difference. Meanwhile another shop just fill it up, and within 10 minutes it is done, clearly not as fill up as using the slow fill. He also did it for free for me, so I always give him some compensation.
quote=marky-d post_id=310945 time=1628279458 user_id=18723]
Although I like the idea of the slow-fill, if it takes 5min to fill 100 bar, I think it would be MORE likely to cause me to over-fill...I'd get bored and start thinking about/doing other things. It seems pretty straight-forward to watch a gauge and shut a valve when it hits 200 bar when it only takes a few seconds. I guess I'm living on the edge, but that should be expected when you're into dangerous things like air guns. :)

marky-d
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