I'm just using them at sub 50psi so they won't need certification under the FRA rules,

I have tried to pressurise them up to 100psi but only got to about 85psi with no problem at all (the compressor could not get much higher).


The way of fixing the copper pipe to the bottle was quite simple these bottles have an opening that is just a little smaller than the 22mm tube so with Gorilla glue or similar, I heated up the copper tube with a heat gun smeared glue inside the bottle opening and gently pushed the bottle over the copper tube and left the glue to set. they are not coming apart!


once you have a standard plumbing tube to connect to all kinds of unmodified fittings become available. I am thinking of having about 5-8 litres of storage for the weapon and the transmission. should be enough for a Feather.