I have a Winchester 1885 that I believe someone has replaced the barrel on. It says “under the forearm” 38-50. The barrel is round, heavy and 30″ long. I do not believe it is original.  The serial number of the rifle is 59536 if anyone can help me determine what it was originally when it left the factory. I am trying to decide if I restore the rifle to the original caliber with a replacement barrel or keep it as is.  Thanks, Richard