TargetTalk

I have trouble filling the 125g tank that is used to decant from a larger source. I have no experience using CO2 in this way. What happens is that I get the gas inside, but as soon as I remove the tank from the, in my case Soda Stream tank, it empties all the gas out. The pin valve will not stay shut. I did try cooling the tank before filling it.

It sounds like the Tau tank valve may be defective. The team I help coach uses them all the time, but filled from a 20 pound tank which has a siphon tube to deliver liquid instead of gas. I'm not familiar with the Soda Stream tanks, but I suspect you have have to invert them in order to get liquid CO2 into the Tau fill tank.

In any case, the valve should close as soon as you remove the Tau tank from the filling adapter.

I wouldnt use bulkfill at all for the Tau.
Its a crime to get a full fill into the Tau as you cant cool it sufficiently like you do with an detachable cilinder (which you put in the freezer). I always and only use 12gr bulbs.

That said, indeed sounds like your bulkcilinder is defective leaking. Is it a new cilinder?

There are several advantages to using the bulk fill cylinder, especially if you shoot a lot. It's even better if you have a team with 16 of them.

1) Without the disposable cylinder in the way, you can get ~ 14 to 15 grams of CO2 into the pistols. Rather than chilling the pistol, you just flip it upside down & let gravity do the work. It can take a few minutes, but you can speed up the process if you hold the pistol upside and fire it once without a pellet. Filling a chilled cylinder using a big vertical tank with a siphon tube is necessary to get the CO2 to go "up hill" and condense inside the cylinder.

2) It saves a lot of money if you shoot a lot or have a team to support. I just refilled our 20 pound tank for $35. That's equivalent to 756 12 gram cartridges. The best price I could find for one hundred 12 gram cartridges was ~$50.

3) It saves a lot of wear & tear on the hardware. Even swapping the piercing caps every time, the O-rings get shredded fairly quickly, and the caps need to be re-built. Once the bulk fill adapter is in place, they can stay put for years before the valve O-ring needs replacing.

I know how it works. Ive had Tau 7s for about 14ish years now..
Money is the only advantage imo.
Only replaced 1 piercercap seal in all those years (and not even from all my Tau 7s).
Never had a complete fill with bulkfill. You can dry fire all you want, its just not as effective as a freezer

I used to shoot at least six different CO2 guns. If properly filled, you can get at least three matches out a filling. Farting around, you can easily get more than enough for a single match without chilling (if you get the cylinder upside down while filling).

Rover wrote: ↑Sat Dec 08, 2018 7:50 am I used to shoot at least six different CO2 guns. If properly filled, you can get at least three matches out a filling. Farting around, you can easily get more than enough for a single match without chilling (if you get the cylinder upside down while filling).

You've clearly never owned a Tau-7. The Tau's don't use a separate cylinder. There is a "tank" in the grip big enough for a 12 gram disposable cartridge. Minus the cartridge, you can get a few extra grams into it. Depending on where the velocity is adjusted, they will average about 7 shots a gram. A 12 gram cartridge will JUST get you through a match with sighters if your pistol is adjusted right.

One problem is that with the new ISSF rules, it's not clear how you can replace the "cylinder" on a Tau every 10 years. They are brazed on...