Originally Posted by PaulD
I had similar problems with mine but perseverance has sorted it. I've found the stripper works great but you need to wrap some shim around the barrel to make it a snug fit and therefor central to the barrel (poor tolerance between barrel and stripper body) I stripped the action and degreased the hammer and the slot it runs in plus polished it and the spring ends. My barrel throws a hissy fit if it's not cleaned spotless every shoot. it is also pellet fussy, it won't shoot Air Arms pellets but for some weird reason loves JSB's which as far as I can see are identical? I changed the firing valve for the newer type (different seal material) but it was one of the first of the long barrel rifles so if yours is newer it probably already has that fitted. I've got a Steyr reg checker and can check it for you if needed as I only live just down the M62 from you. Hope this helps.
Paul thanks for the offer. Having looked into my problem I see u have had a ordeal sorting yours out. Pm me your number if u can so I could compare notes.