You folks need to realize why the lovely blue hued necks happen in the first place on NEW/UNFIRED cartridges.
When the NEW case is extruded, the compounded metal is SOFT.
TO SOFT.
The neck and shoulder areas are heated to a specific temperature and allowed to "air cool"
Air cooling allows the neck/shoulder area to harden, so it won't deform when loading and to increase neck tension.
When we re anneal a cartridge case after several firings, we're doing the opposite. We're softening the brass compound, so we can work it well enough to size it, without it springing back and to create consistent neck tensions.
When I re anneal a case, I do the whole case in a cake pan, in my oven at home.
I turn the oven to its maximum setting and place a pan full of cartridge cases onto the rack.
I leave the cartridges in the rack at the highest temperature for 15 minutes to completely normalize, take them out of the oven and immediately dump them into a sink full of cold water. The cases are now soft enough to size without issues.
This method doesn't get the case metal as soft as the described flame method but it's acceptable and certainly a lot easier. \
Yeah, I've heard all of the excuses for not doing this.
When I was in Brazil in 1976, I went through a facility owned by Mannesman.
They were into all sorts of different things, from mining/smelting to manufacturing and remanufacturing.
They were a conglomerate of companies.
Anyway, one of the things they did, through an affiliated company, was reload military/police ammunition for several different nations.
The only thing they did was to inspect the cases, sort for type and reject damaged cases.
Then they cleaned the cases in a sand/water/muriatic acid mix and inspected them again.
The cleaned cases were then put through a heating process, which was a big rolling oven, heated by natural gas. The oven was tilted so the cases had to move through.
They dumped the cases into a hopper with a vibrator, that allowed them to be fed into the rotating oven, in a manner they would be heated evenly.
When they reached the end of the oven, they dropped into bins fed with a flow of cold water. The temps in that rotating oven were around 500 F (270C)
After quenching, the cases were almost dead soft.
The cases were then lubed/decapped/sized and had their neck/shoulder areas run through a flame and allowed to air cool, to harden the necks/shoulders.
Then the cases were primed/charged and had a bullet inserted.
They didn't care how many times a case had been used. The cases went through this process every single time they were reloaded.
When you're processing several million cases, there just isn't time for all of the niceties.
I don't harden the necks on my cases and it doesn't seem to make any difference. Mind you I'm not looking for enough neck tension to feed flawlessly into full auto firearms.
