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Compressed air cylinders when stored ,fully charged or not ?

Posted: Thu Jul 12, 2007 9:46 pm
by iow
I have a couple of Feinwerkbau CA pistols & due to the very hot & humid summer climate here in south florida I don't shoot them in my screen room or garage ranges for several months.
I keep the cylinders off of the pistols to protect the seals , but I was just wondering if I'm I right in keeping all of my cylinders fully charged for three or four months ?

Posted: Fri Jul 13, 2007 2:00 am
by RobStubbs
I would leave them fully charged if it were me. When shooting regularly they are effectively full or half full for years on end with no problems.

Rob.

Cylinders

Posted: Sat Jul 14, 2007 1:04 am
by JamesH
I believe its better to keep them charged and off the pistol.
Otherwise the seals can deteriorate, dirt and moisture can get in.

Posted: Sat Jul 14, 2007 10:13 am
by Rutty
According to their agent in the UK, Steyr recommend leaving the cylinder on at all times and only removing it for recharging.

Rutty

Cylinders

Posted: Sun Jul 15, 2007 3:35 am
by JamesH
According to their agent in the UK, Steyr recommend leaving the cylinder on at all times and only removing it for recharging.
So what do you do if you have two cylinders?
Seriously.

Re: Cylinders

Posted: Sun Jul 15, 2007 3:43 am
by David Levene
JamesH wrote:
According to their agent in the UK, Steyr recommend leaving the cylinder on at all times and only removing it for recharging.
So what do you do if you have two cylinders?
Seriously.
I think the idea is that you keep the gun's regulator pressurised.

Posted: Sun Jul 15, 2007 4:10 pm
by GaryBF
[quote="Rutty"]According to their agent in the UK, Steyr recommend leaving the cylinder on at all times and only removing it for recharging.[/quote]

My personal experience does not agree with this. I shoot an Anschutz LP@ Junior which has the same innards as Steyr. When I leave a pressurized cylinder attached for a day or more the gun does not shoot properly for the first several several shots. The pellet velocity is very low and the POI drops well below normal. It is as if something in the regulator has taken a set and must be exercised before returning to normal operation.

I keep my cylinder pressurized but [b]not[/b] mounted on the gun.

Posted: Sun Jul 15, 2007 8:44 pm
by pilkguns
I believe there is a little mix up in information here. To cover it all,
1: cylinders can be left full , empty or nearly empty, doesn't really matter
2: The cylinders should be removed from the gun when not in use or ideally unscrewd enough to allow the air to bleed back out of the regulator. The cylinder should be unscrewed to take the pressure off the regulator, as the pressure is what kills both the internal o-rings and the belleview washers inside the reg over time. The less amount of time you ahve pressure in the reg, the longer that part will function before needing a rebuild.
3:Always totally unscrew the cylinder before trying to screw it back in, otherwise you run a very probable risk of pinching the o-ring and causing it to fail prematurely.
4:Wheterh you leave the cylinders on the gun, or off the gun, expect to have to make 3 or 4 cycles of air through the system (shooting with no pellet) before the reg is functiong properly, akin to warming up your car engine. The rubber can stick in either the pressureized or non-pressurized condition and needs a few cycles to function smoothly again.

Thus endeth this epistle.

Posted: Tue Jul 17, 2007 2:29 am
by Rutty
Thus endeth this epistle.
That interestingly enough is what I have always believed. It came as quite a surprise to me that Steyr recommend leaving it in place. When I was told this I did raise the point that no mention of leaving the cylinder in place was made in the manual, but come to think of it neither the Walther (LP300) or Anschutz (2002) manuals make any mention of the matter either.

I have always partially unscrewed the cylinder on completion of shooting as it seems to me good practice. Until I see directions to the contrary i shall continue to do so.

On the other hand, as none of the manufacturers give the issue any attention in their manuals; maybe we are worrying about nothing?

Rutty

Posted: Sun Aug 12, 2007 5:00 pm
by Tim Conrad
Another reason to remove the cylinder: you will never have an 'accidental' discharge. Of anything. After removing, cycle the action a couple of times. I have seen compressed air guns that appear to have a small internal reservoir of air, good for one or two shots after the main cylinder is removed. Even if you don't have a pellet in the gun, a loud 'pop' will get you some nasty looks before prep. Maybe even thrown out.

Posted: Mon Aug 13, 2007 2:20 am
by RobStubbs
Tim Conrad wrote:Another reason to remove the cylinder: you will never have an 'accidental' discharge. Of anything. After removing, cycle the action a couple of times. I have seen compressed air guns that appear to have a small internal reservoir of air, good for one or two shots after the main cylinder is removed. Even if you don't have a pellet in the gun, a loud 'pop' will get you some nasty looks before prep. Maybe even thrown out.
I'm afraid that makes no sense. The first thing you do when unboxing the gun is to screw the cylinder on so you'll be back in the same position - plus you need to do that to go through equipment control. If however your gun handling practices are so unsafe that you worry about accidental discharges then to be honest you shouldn't be shooting in the first place !

Rob.

Some information from a pump dealer

Posted: Mon Aug 13, 2007 8:59 am
by Nev C
Some information regarding leaving cylinders on the pistols can be found here. Apparently there is less wear on the O rings if you leave the cylinders on the guns.
http://www.airgunsonly.com/tech/Handpumps.html

Posted: Mon Aug 13, 2007 10:16 am
by Tim Conrad
That makes no sense ?

I never screw the cylinder all the way in until I'm on the firing line. I put it in place to go through equipment check, but just far enough to lightly touch the o-rings. Most of the shooters I work with do the same. I have seen an 'unloaded' air gun put a pellet in the ceiling. We don't need that.

There is no need to tighten the cylinder until the prep period.

I agree with S.P. on removing the cylinder when not in use. Less stress on the internal parts. And less of a safety issue.

Posted: Mon Aug 13, 2007 11:55 am
by David Levene
Tim Conrad wrote:I never screw the cylinder all the way in until I'm on the firing line. I put it in place to go through equipment check, but just far enough to lightly touch the o-rings.
How do you comply with the last sentance of ISSF rule 8.4.2.6.1 - "When testing air or gas actuated pistols, the propellant charge should be activated."

Posted: Mon Aug 13, 2007 12:10 pm
by Rutty
Another reason to remove the cylinder: you will never have an 'accidental' discharge.
I think I can see what Tim is getting at, if you have a probe loading airgun, e.g. Walther or Hammerli, then if it can difficult to see whether there is a pellet in the barrel or not. This problem can be simply overcome by using a safety line. We use breech flags for smallbore, why not safety indicator lines for airguns?

Rutty

Posted: Mon Aug 13, 2007 1:13 pm
by Tim Conrad
CBI's may be required in the future. CMP and NRA require them now. I have been told that the German Shooting Federation also requires them after an accident at a match a year or so back. If true, ISSF will likely mandate them after 2008, as will USAS. If ISSF does not require them, USAS will not. I don't like the weed whacker line in the barrel unless you can keep it clean. You won't scratch the barrel, you can drag crud into it. There are other CBI's that accomplish the same thing without the dirt potential.

As for 8.4.2.6.1, that applies to air pistols, and should be done at equipment check (trigger weight), and released (unscrewed) afterward. Folks in the UK don't have legions of lawyers waiting to jump out of the woodwork at the slightest hint of a liability lawsuit. Consider yourselves fortunate. One accident could raise liability insurance premiums to the point that many clubs could not afford. We have enough problems keeping our sport alive without that.

Posted: Mon Aug 13, 2007 3:18 pm
by David Levene
Tim Conrad wrote:Folks in the UK don't have legions of lawyers waiting to jump out of the woodwork at the slightest hint of a liability lawsuit.
Believe me Tim, we are catching you up quickly. The compensation awards here may be below those in the US but they are still pretty scary.

Posted: Tue Aug 14, 2007 1:23 am
by .donthc
we are digressing from the original issue here.

the issue is/ was whether the cylinder should be full or empty when not in use, not whether it should be attached to the pistol during storage.

i think what the guy is asking is whether constantly maintaining the cylinder at high pressure will affect the lifespan of the cylinder. Should the cylinder be "emptied" when not in use, to relieve the pressure on the walls of the cylinder?

i usually don't charge up the cylinder (around 80-100 bar) when i am not going to use it for more than 2 days, to reduce the stress on it.

Posted: Tue Aug 14, 2007 1:23 pm
by jipe
Making cylinders fully empty and then again filing them up induce unnessary stress on the cylinder that finally could lead to metal fatigue, so leave them filled. The only reason to make them empty is when travelling by air.

About removing the cylinders from the pistol or not, Anschutz deliver the Lp@ (identical to a steyr lp10 for the frame) with a special orange partially open plastic ring to insertth between the pistol and the cylinder when the pistol is not used => this means clearly that the pistol should not remain pressurized when it is not used.

I also agree with Pilkguns: the cylinder must be totally or almost totally unscrewed before screwing it back otherwise the o-ring can be destroyed. The ring delivered with the lp@ is thick enough to force you to almost completely unscrew the cylinder to insert it.

Posted: Thu Oct 18, 2007 3:20 pm
by somewhereinla
I am fairly new to pneumatic air pistol so I hope to learn more about this great sport from members of this board. However I am a Master Diver (scuba) and know a thing or two about tank maintenance... and maybe able to shade some light about the ultimate way to keep your tank/cylinders in top shape.

_The biggest threat to a tank / cylinders is humidity.
_You should always keep a minimum of 300-500 psi in your tank/cylinders. This would be the ultimate way to keep your tank/cylinders when not in use.
_Never empty your your tank/cylinders completely.
_leaving your tank/cylinders at full pressure will not put any harmful stress on your tank/cylinders... they can take much more. For instance during a hydrostatic test which is use to measure stress on a tank, a 3000 psi tank will be filled to a minimum of 5000 psi with out any damages to the tank. However if humidity did get into your tank, living your tank/cylinders at full pressure would speed up possible damages caused by humidity (that would only apply for long storage scenario (over 1-2 month).

hope this help.