Anneal NOS case necks

[NikA]

I'm familiar with the idea of annealing cases that have work hardened from multiple reloadings. I've also seen old military brass cracked at the case neck, presumably from an aging process in the brass.

I've happened on a number of NOS cases in hard-to-find calibers that I would like to maximize the life of. What is the collective wisdom on annealing before using these new (old) cases? Will it make a difference in the case life?

[15meter]

For hard to find/expensive cases I have annealed new cases before first loading. Won't hurt anything and you are starting with a known state of hardness. Mark it down when you annealed and keep track of the number of firings and you can re-anneal before you lose any to splits.

The question of # of firings between annealings sounds like another question to be asked. Time to do a search so we're not plowing the same ground twice[smilie=1:


Did a search on frequency of annealing, came up with the range of "I wouldn't waste my time" attitude to "I anneal after every firing".

So much for consensus there:coffee:

[JeepHammer]

Older military brass, and old brass in general, has issues...

I would recommend strongly against electrical induction or jet flame annealing, you will heat the iron in the brass too fast. Wartime milbrass had all kinds of trace materials in it, particularly iron & tin.

This is a good time for 'Hot Pot' annealing, with a longer time, lower temp heat soak.
A lead pot with steel shot blasting media and a good old thermometer is a good way to go here.

This will give you your best chance at reconstitution of the brass, no matter how lousy quality it is.

This is one time I would use a heat sink on the heads and heat soak the brass two or three times about 600-650*F before I ran them up to about 750*F.