Quote Originally Posted by maximus View Post
Get a surface use only bottle so tested every 5 years rather than annually. I don't use pcps much but have a 12 litre 232 bar faber steel cylinder that does just fine. 1 fill lasts me 5 years I found id have to travel quite a way to find someone with a 300bar compressor so happy with large volume 232bar. Ex diving cylinders will of had a harder life than the airgun cylinders so I'd look for one of them personally.
Have you ever done the maths on how much more air is in a 300bar ?

1bar = 1volume, so assuming a 12ltr cyl, the 232bar contains 2784ltrs of air, a 300bar 3600ltrs,

airguns need to be refilled at around 120-140bar but as the cyl empties you will only equalise the pressure between cyl & rifle, so between 1440-1680 ltrs of that air in effect cannot be used, because it's under 120-140bar.

So in practical terms a 232bar 12ltr contains between 1104-1340ltrs of useable air, a 300bar 12ltr contains 1920-2160ltrs that's a lot more fill's/top up's.

caveat;
That is theory, air at pressure is funny so the figures don't actually work out exactly.