question on filling co2 tanks.

[DaXtremeist]

my friend has a large co2 tank that we fill off of but whenever we let him fill them they don't get as full as if we were to go to the pro shop. and the pro shop uses the same tank and tank setup as we do. im looking into buying a scale to make sure we fill them all the way.. but i don't reall know how to tell when they are full.. do i just weigh the tank. then fill it with the correct amount of co2? like 20oz

[cphilip]

Well sort of. Usually you let the residual out which does two things. It cools the tank so that it will fill with a bit more liquid CO2 rather than gaseous CO2 and it gives you an empty weight. So you can then fill with the right number of ounces. Most do not fill full to capacity as you will give little room for the liquid to turn to gas in the cylinder before entering the gun. You don't want that so you leave a bit of room for gas production. For example a 20 ounce tank you might put only 16 or so ounces in from empty weight (Tare)

Also remember there are two types of fill cylinders. One with a bottom straw and one without. The one with the bottom straw can be used upright but the other should be inverted. As you want liquid CO2 to run into the cylinder not gas, Or you will not get a very good fill if it does.

[This message has been edited by cphilip (edited 08-23-2001).]

[DaXtremeist]

thanks... i will see if we have a bottom straw in the tank i doubt it .. hrmm so that means we have to invert a 300 pound tank : )

[cphilip]

Oh my! you gotta see about that pickup straw. All of our CO2's are like 30 - 40 pounders (2 1/2 to 3 foot tall?). They weigh about 60 pounds tops. Most times we can get a straw equiped tank. But we made a wooden rack for the times we have to make do and invert one. Might want to see if you can exchage the big one for few smaller ones. Or get one with the straw.

[krafty]

If you have an empty, warm tank, it often helps to fill it with just a couple oz. of co2 and swish it around a bit, then vent it all out, then fill the tank. As cphillip said, you can get a bit more into a cold tank. Just don't put too much in, or the co2 will freeze solid as you're venting it and you'll end up with a chunk of dry ice in the bottom of the tank.

I can't believe that a 300 pound co2 tank wouldn't come with a dip tube...

krafty

[Bearshirt]

<font face="Verdana, Helvetica, sans-serif" size="2">Originally posted by krafty:


I can't believe that a 300 pound co2 tank wouldn't come with a dip tube...

krafty</font>

Yeah it must have the dip tube. You guys would have noticed right away, without the dip tube you would only get gas, no liquid.
You can also put the tanks into the frig after filling it the first time. Once the tank is chilled you can put in the full amount. Don't be tempted to over fill, it will only blow out your burst disk and you lose a day of playing. Happened to a friend, and nobody had an extra disk.