Carbon, Manganese, Sulpher and ??-- Not a metallurgist by any means, just wondering. If you'll pay the shipping cost from MI to AZ- I'll send you a "boat anchor" 1903 era 12 gauge R frame receiver OO grade- I also have the parts intact from same: bolt, coupler, top lever,
WPS, as found on my M21 and most of my M12's-- nickle based, chrome moly- most likely 4140-- But why do the bottom of the early M21 receivers turn a brownish hue and years of field usage, but the barrels, etc. retain most of their rust bluing?? RWTF
