I seem to recall reading many years ago that a way to do this by hand, and keep the case head from annealing is to put water in a large rectangular cooking sheet with raised edges, deep enough that the case can be stood up with the head in the water, then heat with a torch going round and round. Then, when the case is the right color you just tip it over into the pan of water.

I was afraid that the quick cool off by the water would defeat the reason for annealing, to a degree. I'm certain this is the case with iron, but with brass, evidently not.

Thanks for the helpful replies.

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