The big guns in the knife business have a metals page on their website. Look at Benchmade and Spyderco for example. As with everything else, it's a trade-off. For knife blades no stainless steel is as good as carbon steel for strength and edge-holding. If rust is not an issue (either by climate or by your attention to maintenance), go with a tried and true carbon steel like 1095. If you want stainless (which resists rust but is NOT rustproof), look at the current offerings on those websites. A hot all-around stainless steel knife metal for the past couple of years and still going strong is S30V. BTW, the "HC" in 420HC is for High Carbon.

No matter what the metal, the heat treatment it underwent is extremely important. A lesser steel heat treated properly will outperform a higher-end steel not properly heat treated.

Good luck with your search.

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NRA Life Member