My 160 Pellgun still uses the two 12g Co2 cartridges with a drop of oil on each tip. They've been at about 50% pressure (900PSI max) for about a month now in the gun rack next to me. No leaks, no complaints. It usually gets shot dry frequently anyway. It's so darn purty, balanced and accurate...well, heck, workin' that bolt action is cool! Has a nice, quick sorta double click to it too.
But, anyway, like the 760 Powermaster, it needs a lil gas to keep the seals in good shape, it seems?