Years ago, when copper was still cheap, I bought a 50" length of 2" copper pipe. I soldered a cap on one end. I clamp the pipe vertically in my portable workbench, with the capped end on floor of the garage. I stand two propane torches on the ground opposite each other with the nozzles about two inches from the side of the copper pipe. I suspend the barrel (with the muzzle plugged) in the pipe with an S hook fashioned from coat hanger. One end through the tangbolt hole and the other around a dowel placed across the top of the pipe. After boiling, I just lift the barrel out of the pipe (make sure the ceiling is high enough if indoors) by the coathanger and carry it into the basement, hang it from a joist to cool and card. No need to handle the barrel at all during the entire process.