Hard to say. A lot depends on whether it was BP or a substitute, whether it was stored in dry or humid conditions, was it a stainless barrel. You might get lucky. Give it a good cleaning, and check it with a bore light. If there is rust, fine steel wool wrapped around a cleaning mop, along with some gun oil should clean it up. If it is pitted, then test fire it. It might still shoot well. If not, you might want to try "fire lapping" it. There is a kit you can get from Brownells that contains several grades of abrasive paste. You apply it to a number of pure lead conical bullets, and fire them thru the gun. It smooths the bore, and can restore the accuracy of a damaged barrel.
Larry