Many 1903s were returned when M1s were issued. These were often rebuilt and put in coz and linen then stored for future use. This is the history of mine which has an 8-43 barrel on a 1932 receiver. I had the thrill of unwrapping this beauty. Barrels were often replaced due to the nature of the primers used at that time. Most likely, the real damage to the barrel was the use of steel cleaning rods at the muzzle end.