Went to the Missoula gun show and found a highwall castings to make a replica. I was told it was put out by a company called "Bolder River Foundry". No instructions on assembly, but not too worried about that. Does anyone know what the steel the foundry used in there castings? 4140, or 8620 are the two that I am familiar with for heat treating. But would like to know for sure what it is. I have a 45-70 barrel already on hand for the rifle. It will be a good project for next winter. Best regards, the toolman.