Casey,
Here are some quotes from the GGII chapter on annealing:
"Brass anneals at temperatures as low as 480 degrees, but the process takes much longer. Even annealing at 600 degrees requires an hour, far too long for our purposes. Instead, we want to quickly heat necks to just under the melting temperature of zinc [787 degrees], more than 1000 degrees under the melting point of copper. Over-heating brass can actually melt out some zinc, turning the brass permanently soft.
"Annealing brass doesn't involve heating to a single, precise temperature. In a way it's like cooking pork: Many people "know" pork needs to be heated to 160 degrees Fahrenheit to kill trichinella larvae--but 160 degrees is merely the temperature that kills the larvae within seconds. Cooking pork to somewhat lower temperatures for longer periods also whacks 'em."
Which is why I discuss several methods of annealing in the chapter, and their advantages and disadvantages.
