Same here. I often clean the necks right after firing while the barrel cools.
If it was dezincification due to heat you would see it on the shoulder. Strange your cases don't have it on the shoulder but just below the shoulder on the body? For several years I have been looking up articles on dezincifiction during annealing. All the articles I can find are dezincification in chemical solutions. Almost impossible to find a good scientific article. I ignore personal opinions. Amps on their website says it doesn't happen. I have never seen pink anywhere on a case after annealing with a torch for many years. I have intentionally over heated several cases to check for loss of hardness. Some people say that if you leave it in a flame to long you will see a yellow color in the flame. It isn't zinc burning off. I have a good article somewhere explaining the yellow color. Have you cleaned the neck/shoulder area with steel wool and then wipe with alcohol and see if it goes away. Did the cases ever have case lube on them. What brand? Try another type lube. I use a light vis petroleumm oil. If dezincification due to heat was occuring it would happen to all of the cases. Slight variation in alloy composition should have no practical variation in properties of the brass.
This is the right answer.
All the cases were straight from being fired. They were not tumble cleaned yet, and none of them had any kind of lube on them yet.
The question is will the zinc being bleached out weaken the brass, or somehow else affect its strength or mallability?
You have not proved that zinc was removed. Repliers are quessing. Even if there was Zn loss which I doubt how much would you loose in a couple seconds at temperature. You cannot melt the zinc at the melting temp of zinc it melts at the melting temp of cartridge brass. It's a homogenous solution without any secondary phase groups floating around.
Absolutely it will.
Iosso liquid brass clean does it too if left too long in the solution.
yep thats what i do as well when i remember to take some 0000 with me.
You're looking at the result of a redox reaction on the surface of the brass, maybe a molecule or two thick. Zinc is not being leeched or smelted of the brass alloy to any significant depth. As an example, the "pink" color you observed after annealing can be generated in brass prep after brass prep by using too much Lemishine, low pH, or other chelating agents. It does not hurt anything other than the psyche of those that witness it. A single cleaning without excessive Lemishine/acidity/chelating agents is usually all it takes for the pink color to disappear. I understand that it is an unusual thing to see when it is first observed and that it may cause concern, but it's not a problem.
Not trying to be rude but how come no-one else seems to have this coloration when annealing. I still think it's strange that it only happens to a few cases out of the same box. If it's heat causing a problem from annealing you should see it on the shoulder and not only on the body below the shoulder?
This is the third time annealing them. This never happened before.
