incomplete filling of anschutz 8002 cylinder

[Ltdave]

brand new scuba tank with full charge of air...

no leakage at the filling adapter or the yoke...

i can usually only get 2/3 of the rifle cylinder full (based on the manometer)...

is this because the cylinder set up to hold higher pressures if coming off a compressor system?

[Andre]

Is your cylinder 4500 psi (walther) and tank 3k? If so then the tank will only fill to 2/3rds capacity.

[TerryKuz]

Your cylinder should reach equilibrium with the fill tank. A good guess is your manometer on the Anschutz cylinder is faulty. I imagine the compressor fill gauge matched the tank gauge, so those two gauges would seem to be reliable. Try to fill another air gun cylinder and see how that reads. Pressure gauges in general have a pretty high replacement rate.

A second issue may be an overflow cutoff. If you are rapidly filling the cylinder, it may cut off. I really doubt that scenario, but I thought I would mention it. Good luck.

[David Levene]

As the 8002 has a 200bar cylinder I can only think of 3 possible reasons (others might think of more):-

1) They didn't completely fill you new Scuba tank
2) The gauge on you cylinder is faulty
3) Your cylinder is fitted with the wrong gauge

[BigAl]

I would be pretty sure you did not get a "full" fill. Many places will fill your cylinder until it hits the full mark, and just hand it back to you while still warm. To get a full fill you really need to let the tank cool right down and then top it off. If you are trying to fill the gun cylinder to 200 Bar from a 200 or 207 bar scuba tank that has not been topped off you will never actually get 200 bar in the gun. If you really need to fill to 200 Bar then you should really be doing it from a 300 Bar tank, and using the gauge on the fill kit only to measure the pressure, the indicators on the gun/cylinder are notoriously unreliable. About all they are good for is knowing when you should refill the cylinder before the pressure drop might affect the velocity output of the gun. You would want to figure out that pressure by trial and error. Once you have an idea what reading on the gauge is needed, they are reasonably OK on repeatability.

Alan

[dc.fireman]

I would be pretty sure you did not get a "full" fill. Many places will fill your cylinder until it hits the full mark, and just hand it back to you while still warm. To get a full fill you really need to let the tank cool right down and then top it off. If you are trying to fill the gun cylinder to 200 Bar from a 200 or 207 bar scuba tank that has not been topped off you will never actually get 200 bar in the gun. If you really need to fill to 200 Bar then you should really be doing it from a 300 Bar tank, and using the gauge on the fill kit only to measure the pressure, the indicators on the gun/cylinder are notoriously unreliable. About all they are good for is knowing when you should refill the cylinder before the pressure drop might affect the velocity output of the gun. You would want to figure out that pressure by trial and error. Once you have an idea what reading on the gauge is needed, they are reasonably OK on repeatability.

Alan

This. I deal with this issue in my normal work environment on a semi-daily basis. If you can absolutely confirm that you received a cooled cylinder back from your local filling station, then it would be time to check the manometer (gauge) for a faulty spring, or sticking needle.

[yana]

Even without cooling its perfectly possible to get the gauge at 200 bars with enough scuba pressure. It only drops áfter cooling down.
I have gauge issues with my Aeron Spider. It never shows more than anout 160 bars, even with full fill

[Rover]

With my Walther LPM1 SSP and old Steyr LP1 cylinders I don't have these issues. (snicker)

[TWP]

My vote is the manometer on the rifles cylinder is not accurate.

Simple test, fill another cylinder from your tank and see what it registers. Or tank your cylinder and try filling it from a different tank. Or buy an gauge for your tank.

I've had many shooters and coaches at the range complain "Your tank is empty" I screw on my gauge and it reads 2,500 PSI or more, yet their cylinder shows almost empty. I've seen several cylinders that you could shake and the face behind the gauge needle would move around.