Fighting knives require a tough and strong steel, preferably with good rust resistance as you don't want to baby it. 12C27 fits this bill PERFECTLY! Great rust resistance and a fair edge. In a fighter edge retention is not the top need. Ka Bar went to this steel for the KA Bar stainless fighting knives and BM use it in the famous BM42 Balisong knife.
Same goes for a utility knife, however as tough and good as 12C27 is as a steel, it does not hold an edge amazingly well. With a good heat treat it can work very well (so I have been told none of mine were better than 440a or 6m/6a steel for edge holding, but tougher) My blades in this steel were mostly small folders (Big Swede, super Swede etc) Sorry bout the spelling! I also used a 12C27 Ka Bar knife as well. I tried it next to me 1095 steel Ka Bar knife and to be honest the 1095 steel knife held an edge about 40-40% longer for me in chopping and cutting boxes. However as both are primarily a FIGHTING knife I would prefer the rust resistance of the 12C27 over the 1095 steel. I as a result of trying the 12C27, went for the D2 tool steel model blade, as I liked the ergonomics of the knife, but wanted a better performance steel. Rust is a problem with D2 though
For a utility blade I would look at a steel like 440C or 10A as a good start, with ATS-34 BG-42 et al as a more advanced and high end user steel.
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Wayne.
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