Make a long story short: Crosman's customer service has sent me (4) $60 scopes and various mounting rings. All of the scopes (their bulk scopes supplied with higher priced rifles) have been defective. I've also found that the ring screws loosen after a few shots. I think I have a few solutions. One is to finally get a good scope from them (they'll supply it) and loctite the mounting screws. which I don't really like. The other is to start all over with mounting bases/rings. I'm thinking of getting Warne scope mounts which I think handle air gun recoils and stay put once installed. My rifle has dovetail base and I think the Warnes will fit it. You guys can let me know. Any advise will be appreciated. The gun is a Crosman Optimus and i also have a GAMO WHISPER.