The most commonly encountered use of the term, "Decarbonized Steel" for us of a double gun ilk, is the barrels for the lowest grade of E. Remington & Sons and Remington Arms Co. hammer doubles. We just had this discussion over on the Remington Society of America board and Charles Semmer who wrote the book on Remington doubles posted this -- "Hap, This is probably more info than you figured you would get. There is a difference between decarbonized and Remington Steel. I don't know the content of Remington Steel but assume it is much stronger than decarbonized, possible containing some carbon. From a letter I have of a man (deceased) who was the associate curator of History at the Rochester Museum of Science Center. He was a historian. This from his letter explaining the origin of decarbonized steel. "The Englishman Henry Bessemer filled a big heat proof retort---The Bessemer Converter---with several tons of molten pig iron and then introduced a blast of air. With this supply of oxygen, the carbon content of the pig iron ignited (carbon burns readily as in coal) and burned out. The resulting material was "decarbonized steel". This was the same thing that we call mild steel today. It is the material for wire nails, auto bodies, paper clip, structual steel, and thousands of other products today". The letter goes on, " I suppose, though I really don't know, that modern shotgun barrels are made of some sort of alloy steel of higher strength than plain mild or low carbon steel. If so, that would be an argument for using only low-pressure loads in a "decarbonized" steel barrel". I think of this steel as being soft like Damascus. You'll see a lot more repairable dents in these steels than in a more modern steel."
Here is the link to that whole topic --
http://www.remingtonsociety.com/forums/viewtopic.php?f=6&t=2097
