due to the soft projectiles that are used for rimfire, usually there may be leading of the barrel but not a worn out barrel. a good cleaning may produce a very good bore. Many i have shot had just about no ridges showing but accuracy suffered very little. Mainly pitting would be the worst senerio i can think of. Other than this, the headspace can affect performance and safty, or broken bolt components can render it useless if no parts are available.
ask the vendor for a return policy if the gun is really not what you expected or if it is broken. But remember also you are dealing with ,no doubt, a very well used gun. Well used does not mean abused and can turn out to be a treasure.
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