I picked up a used heat treat furnace (Cress) at an auction for
cheap. Still works.
After rails installed and holes drilled. I take the raw receiver and ramp it
up to 1600 F Quench in cold brine, (room temp).
Then take it back up to 750F shut off furnace and let it decline over
4-5 hours. Boy, this is the greatest thing since lincoln logs.