You have to be VERY careful if you **DO** anneal any brass. And, only ever anneal the necks only on rifle brass. NEVER (and I do mean NEVER) anneal any pistol brass. Annealing pistol brass will make them too soft, and they will become BOMBS.
If you are going to anneal rifle brass, be sure to only anneal the neck area that touches the bullet. DO NOT anneal the main body of the brass. The discoloration that you see on some military brass is heat "wicking" from the neck area only. Only the neck that holds onto the bullet should be annealed.
Here's what I tell students:
" If you only have 5 pieces of brass to your name........... you'll find some way to keep them going. However, if you have a good supply, just keep reloading until they split or otherwise fail"
I have never annealed a single piece of brass to reload it. And, that's tens and tens of thousands over the years.