That's right, and for all we know that carbine may have been pitted by exposure to sea salts in the PTO. There are any number of circumstances under which this may have happened, one being that the carbine was dropped by a casualty on the beach and picked up later and stored without washing with drinking water. It may have been put in a leather scabbard wet and left for a time. Normally the damaged parts would have been replaced or the carbine parted out, but perhaps it happened near the end of the war and the carbine was 'brought back' and put away.