Annealing/Quenching Question

[bonza]

When annealing cartridge cases is it necessary to water quench, or is air cooling adequate? Any pros or cons to either method?

 

[BHarada]

I'm about ready to start annealing my brass now that replacement brass is getting so hard to find. From what I've been able to learn, after multiple Google searches on the matter, is that how fast brass is cooled does not affect the annealing process as it would for steel. The water quench is more to prevent the heat from migrating down to the case head, which must not be annealed. That said, I've watched videos of the automated annealing machines and all of them air cool the brass.

For me the only con to water quenching is having to dry off the brass afterwards.

 

[Slamfire]

I'm about ready to start annealing my brass now that replacement brass is getting so hard to find. From what I've been able to learn, after multiple Google searches on the matter, is that how fast brass is cooled does not affect the annealing process as it would for steel. The water quench is more to prevent the heat from migrating down to the case head, which must not be annealed. That said, I've watched videos of the automated annealing machines and all of them air cool the brass.

For me the only con to water quenching is having to dry off the brass afterwards.

Excellent reply. Steel, the rate of quench will trap carbon inside or outside the crystal, making a huge difference in material hardness. Brass, the only way you harden is by "work hardening".

Heating either steel or brass and letting them slowly cool will soften them. For steel the process is called “normalizing” .

It might be overly conservative to water quench, but you absolutely do not want to anneal the case head. You can look up terms such as quarter hard, half hard brass, as a general rule US brass was quarter hard, and can see that softer brass is real ducticle .

 

[rayatphonix]

I have been annealing for several months now. I can handle the brass near the base with bare hands within about 10 seconds after removal of the flame. Quenching just makes a mess.

 

[MEHavey]

1. Quenching does nothing to brass, except make it wet.
2. Normal annealing (neck/shoulder only to 750°) will not heat-creep much of anything to the base
2. Use a deep socket as a case-spinner in a cordless drill and just dump the case onto a dishtowel* after the neck reaches temperature.
4. I heartedly recommend using TempiLaq to judge temperature, and not your eyes.





* (preferably not your wife's favorite)

 

[bonza]

Thanks guys, great replies which concur with my findings.

 

[docsleepy]

I may be wrong, but I just do it by eye instead of using the temperature sensitive paint.

But I get the room completely dark (a tiny neon night light only, and I do it after sunset), wait until I can see the paint cans on my shelf in spite of the darkness, then start the propane torch, with about a 3/4" inner blue flame.

Turn cases using sockets (WISH I had deep well! that's a great idea)

Stop at soon as I see any beginning of deep red. This seems different with larger rifle cases compared to the relatively small .223 which gets to temperature very quickly. You can also see a change in the flame, around the case, which goes from blue to blue with red/orange in it.

In my case, when I was squeamish and stopped early on some, I had more dispersion in point of impact, than when I was aggressive and got all the cases to observable deep red neck color.

Drop in water (yes, messy.) 30 minutes in oven at 200 degrees to dry.

I experimented with running the expander ball of the full length die five times up and down the neck (to pre-harden it) in an attempt to hit some happy medium, but I'm not sure it made any difference.

Once I got consistent at the annealing process, my vertical dispersion in my 7mm08 was decidedly less! Big improvement in a pencil barrel hunting rifle...

 

[jmorris]

2. Normal annealing (neck/shoulder only to 750°) will not heat-creep much of anything to the base

yep, of you spot correctly it is no problem; however, if you do it wrong, water can at least keep an over annealed case from being dangerous.


You don't want any "glow" of the case. Not red, not even dark red and no orange case glow.

The easy way to set up with a machine is to start the machine running too fast and slow it down until you have proper annealing with out the flame turning orange.


This Video shows too much. Notice the change in flame color.



This video is what you want. Flame remains blue the whole time and case is cool enough to pick up right after the flame.