"Swains Spring Service" Great Falls MT, Jeff Carlisle is a good guy. Jeff has stocked and supplied several different steels for Damascus and several powders: 1084 grit, 4600E, and 1018. He has been making and garanteeing springs for 30 years out of 5160. He sells 15N-20 sheared by Kelly Couples, very nice material as it is sheared to the exact size we use...Ed