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rsterne · Moderator

I thought I would post a very simple conversion that can be used with either a 9 oz. CO2 tank or a 13-18 ci. HPA tank with regulator.... The tank acts as the forestock.... It should be secured to the 2260 tube at the back with a worm drive clamp (and spacer if necessary).... to prevent rotation and take the strain off the pipe fittings....

It uses a 2260 tube, with a Disco fill adapter.... plus two STEEL (not brass) 1/8" NPT pipe fittings, a "Street L" and a "Hex Nipple".... The valve is a standard Paintball Fill Adapter with valve and safety vent hole.... You would have to use a Disco valve or a valve with an O-ring to seal the front end.... and it would have to be secured properly into the 2260 tube to take the end force safely.... If used on CO2, you can remove and replace the tank without any disassembly of the gun....

The 2260 tube has a safety warning roll-stamped into the side of the tube.... This weakens the tube, and this area should not be pressurized.... an extended valve front end such as that available from Muzzle Mack should be used.... http://muzzlemack.com/default.aspx .... I would even use this on a CO2 installation for safety.... and it is a must for HPA use....

The valve must be located properly to withstand the end force of the HPA (or CO2) in the 2260 tube.... If you use a Disco valve, install it as in the Disco, with three screws in tight fitting holes so that all three screws carry equal load.... You should run a 1.8K low side burst disc in the regulator to limit the pressure in the tube to 1800 psi in the event of a regulator failure.... This means that the highest pressure regulator you should run would be 1400-1500 psi.... The gauge and fill fitting on the regulator will not miss the 2260 tube when rotated.... so you must assemble the tank, valve, and pipe fittings first.... install the Disco fill fitting into the 2260 tube.... and then screw the Disco fill adapter to the male threads on the "Street L" last.... stopping when the tank is under the tube of course.... All pipe threads must be sealed with at least two layers of Teflon Tape.... more it you need it to get the proper orientation....

While I feel that this installation is safe if properly done.... I accept no liability nor do I recommend that you make this modification.... I present it only as an example of what can be done....

HPA IS DANGEROUS.... PROCEED AT YOUR OWN RISK !!!

Bob

AirGunEric · Site Admin

Interesting, minimal effort conversion!

Using the Disco valve- does it's body cover the stamped portion of the 2260 tube (as in, by using the Disco valve, the stamped portion being weaker is not as much an issue)?

rsterne · Moderator

The front of the Disco valve is not long enough to cover the roll-stamp.... Neither are the B&A Boss or Mountain Air bulk valves.... That is why I posted a link to yourdaddyjoe's extended valve front end....

I know that valve extension is one of Joe's top sellers.... This conversion may make it even more popular.... Maybe he should offer it with a 2260 tube drilled for a Disco valve as a set.... Wink

Bob

yourdaddyjoe · Supporting Member

I'm out of brass... and extended valves...

I just stocked up on T6 and some new tooling... so I'm broke again...