Talk:Handloading
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An anonymous user at 69.243.38.8 removed the information on heating and quenching the brass to anneal it, with the following comment:
(→Maximizing case life - Removed bad science on annealing.. quenching does not stop the annealing process... it prevents it.. annealing requires the item cool s-l-o-w-l-y, quenching causes hardness)
While slow cooling is the processed used to anneal steel (since you want the grain strucutre in the annealed steel as large as possible), brass is a different matter. Once the brass reaches 660F, the work hardening has been undone, and the cooling doesn't really have an impact on the hardness of the case mouth. The quenching is done to prevent heat transfer to the base of the case, which should remain harder than the mouth. Calling this process "annealing" is slightly misleading; what is really happening is a from of controlled heat treatment. Just like tempering steel, you carefully raise the temperature to the level which will reduce the hardness to the desired level, then you quench immediately; leaving the metal at the tempering temperature too long will "age" the metal, and reduce the hardness further. In fact, quenching doesn't really stop the softening process, it merely slows it down by many orders of magnitude. Even at room temperature, metals will loose their hardness over time, but as the time/temperature curve is exponential, it will take thousands of years at least before the loss of hardness becomes noticable. scot 14:48, 30 May 2006 (UTC)