Originally Posted by
angrybear
Yes, if you're sure it's empty, not just a duff gauge on the rifle, so cock & dry fire it to check
Provided it is empty, cock the rifle (to take any spring pressure off the firing valve), connect the cylinder & open the cyl valve,
Now if the fill valve is a bit stuck you might want to give the cyl valve a good turn open (as much twist as you can do in one wrist move) rather than just try to crack it open, so that the initial pressure hits the valve hard,
but once it opens start to close the valve to slow the fill speed.
Always keep your eyes firmly on the cyl pressure gauge while filling, it tells you everything you need to know.