I just thought I would share with other forum members. Best Fittings now do filling adaptors for Steyr, Walther, Hammerli and Rohm pistols which allow you to connect the adaptor to the air cylinder before connecting to the air bottle to charge it up and also allow you to bleed the the charging system before you disconnect from it. This takes the pressure off the threads on the charging adaptor and also the air cylinder for the pistol and means that if you charge it up to 200bar, that is what you get without the frantic turning of the cylinder to get it off the adapter before you lose all the air you just put in! Costs just £14.58 plus vat and post.