Brass case annealing

[Doug Lee]

Hello All,
On another forum, a thread called "Candle Annealing Testing" caught my eye so I started reading the responses, what ever the heat source some say they heat the case for X seconds, then just drop it into something safe with no water and let it cool slowly.

Doesn't the water quench allow the brass to soften, thereby reducing stress?

Does the rapid cooling cause the desired molecular change, like when dealing with ferrous metals, the blacksmith quenches (to harden) when the final form, shape is achieved. (hardness returns to the metal)

With non-ferrous metals does the quench causes the magic to happen?
(softened / stress relieved)

Doug
*

 

[Unclenick]

Doug,

Brass is only hardened by working it. Heating and quenching do not harden it the way it does carbon steel. Quenching might terminate the effects of a heat source a little faster, but mainly water is used in annealing to make the brass possible to handle quickly, to help clean soot off brass, or a shallow quantity in a tray can protect cases standing in it from having the annealing heat affect the hardness of the heads.

 

[Doug Lee]

When annealing does the softening occur to non-ferrous metal during
the heating or cooling step?
Thanks,
Doug
*

 

[Unclenick]

Heat mobilizes things, so it happens when it is hot. Think of room temperature as the deep freeze for brass, where nothing changes much, but higher temperature allows movement and change.

I just added a post to the thread you found at THR. I seldom post there (6 posts over a number of years), but it seemed like an appropriate occasion to do so.

 

[ligonierbill]

Almost all plastic deformation in metals occurs by the movement of line defects called dislocations. (Some metals, brass included, will "twin", but that's not relevant here.) As these dislocations move, they interact, essentially tangling up and creating internal stresses. That's work hardening. When you heat the metal, the atoms move more freely, allowing these internal stresses to move the atoms, thereby reducing the stress. Like releasing a spring. The term "stress relieving" is often used. As has been noted, cooling simply stops the movement and release of internal stress. Of course, if you get it too hot for too long, other changes will occur that soften the brass to the point that the case cannot be used. But that is unlikely to occur using common DIY annealing methods.

 

[Doug Lee]

Thanks for the answers and the extra effort to help me understand the science of it.
Doug
*

 

[akinswi]

Doug,

As other have stated the science above if you do decide to anneal that way

I have annealed cases both with a candle flame and propane torch. From my experience I couldn’t tell a difference in accuracy or case life using either method but Im shooting from service rifle not a 1/4 moa bench rifle with that being said

I can tell you that you will not typically see the case discoloration with the candle flame as you do with the torch. But I can tell you that you probably will not ever over anneal the case using the candle because it will burn your fingers before it does. You can over anneal a case with a propane torch anyone who has ever annealed this way has and you will too , so practice with cases you dont mind destroying at first

The similar article I read was around this premise.

But If you want professional results a machine annealer , Amp is the best will give the most consistent results in my opinion. (your fingers will thankyou.)

 

[Doug Lee]

Thanks to all for the input.
Doug
*

 

[Nick_C_S]

Quick topic drift . . .

I'm new to loading 223.

I know annealing softens the brass. But what is the point in terms of loading ammunition?

So far, I've loaded several hundred rounds of 223 Rem; and, so far, I fail to see where annealing comes into play here.

 

[ligonierbill]

Usually a case ends its useful life with a split in the neck. Annealing may extend case life. Personally I don't think it's worth the effort, but some folks disagree. When I get the occasional split, I just discard and move on.

 

[Nick_C_S]

Annealing may extend case life.

Okay. So it relieves the effect of work hardening to extend case life. An optional process. Got it. Thank you.

 

[akinswi]

Nick C S,
Look for videos of Long Range Shooters on youtube annealing vs not annealing and you will see the difference. If your just blasting ammo its not important but if your trying too shoot scores , smaller groups etc etc it helps with consistency, If the best shooters in the world are doing it , means its helps

 

[gwpercle]

The brass sofening occours during the heating ...dropping it in cool water just allows you to pick them up sooner .
You can heat them and let them air cool , no difference .
When using a propane torch , you can over-heat the brass so dropping into water simply stops the heating process faster .
Brass doesn't quench harden like knife steel does .
Gary

 

[Doug Lee]

I was under the misconception that the quick cooling (quench) did the softening
on non-ferrous metals.
Thanks,
Doug
*

 

[Marco Califo]

Nick, re: annealing 5.56/223, no real need. 7.62/308, and 7mm mag, 300 WM, it is more important.