Filling c02 paintball tank

[vnoz]

So I Purchased two 20 oz paintball tanks and the tank adapter to hook up to a regulator and now my question is about filling them... I know I can just take it to a sporting goods store and fill them for a few bucks.. But can you actually use a bigger c02 tank to fill these? Or is it not possible since the regular c02 tanks aren't liquid c02?

 

[EFaden]

There are two types of CO2 cylinders... siphon and non-siphon. All CO2 tanks store liquid. The siphon style draw the liquid off of the bottom instead of the gas off the top. You want this style if you want to fill another tank. If you are using the gas through a regulator you want non-siphon style (liquid + regulator => BAD). If you want to fill a tank off of a non-siphon style you can connect them directly (e.g. without the regulator) and flip the non-siphon one upside down or at least in theory.

 

[Chrisl77]

If you are going to fill your own tanks you also need a co2 fill station and a scale to weigh how much co2 you are putting into the tank.

 

[shortyjacobs]

I fill my paintball tanks off my big tanks all the time, (for the home draft setup I have in my sig). I bought a CGA320 nipple from a welding supply store, and cobbled together my own fill station using some old paintball equipment, (a remote line), and my hops scale. I just flip my CO2 tank upside down to get liquid, and secure it so it can't fall on the valve. Works great.

Easiest way to do it, since my setup cost nearly as much, is to buy a fill station on ebay. They are like $30. Search "CO2 fill station" on ebay, you'll find something like this:
http://www.ebay.com/itm/Paintball-C...aultDomain_0&hash=item483ed4d497#ht_938wt_881

Hook it up to your CO2 tank, flip the tank over, connect the paintball tank, pump some CO2 in by opening the tank valve and valve #1 on the fill station. Then close Valve 1, open Valve 2 to vent the paintball tank. This chills the paintball tank down so it can accept liquid CO2. Once vented, close valve 2, open valve 1 again, and put the right amount of CO2 into the paintball tank. (For a 20 oz tank, put in 15-20 oz). Do NOT overfill the tank...a 20 oz tank can really hold something like 50 oz of liquid CO2, but it needs headspace so the CO2 can expand with heat. If you overfill the Paintball tank, it can either explode or at least blow the overpressure relief valve. You want it only about 40% full of liquid, leaving 60% headspace, IIRC, which means only put 20 oz max into a 20 oz tank, (that's why you need a scale).

Good luck!