Case annealing then cooling it water does not seem right.

[gonzoo75]

I was reading some ways people anneal cases. Some of the practices dont make sense to me being a welder and having a limited understanding of metallurgy. I know that in our industry when we want to harden a metal we heat it up to what ever temp required for that metal then rapidly cool it. To anneal we bring it up to temp and cool it down slowly making it softer and more ductile. So when i read that people heat the cases up and dunk them in water. Is that not defeating the purpose?

[rantingredneck]

as an amateur bladesmith that also doesn't make much sense to me.....

[gonzoo75]

I just answered my owen question. I went and got one of my old text books out. Looked it up in there it state that with copper and brass that quenching with cold water is sometimes beneficial. I wonder if this is the case with rifle brass?

[PawPaw]

Originally Posted by gonzoo75

when we want to harden a metal we heat it up to what ever temp required for that metal then rapidly cool it.

That works great for steel and steel alloys, and for many iron alloys. Brass is different. The only way I know to harden brass is to work it. Hammer it, bend it, stretch it, and it will get harder. Heating it tends to soften it and water quenching doesn't seem to affect it.

[gonzoo75]

Thanks for the insight pawpaw

[k4swb]

Brass cases are softened by heating and cold quenching. Opposite from steel.

You usually want to do just the necks and maybe the shoulders. Some new unfired rifle brass will show a discolor at the neck and shoulder and this is what was done.

Soft neck good.

[Brian Pfleuger]

Quenching the brass in water has no effect on the annealing process, good or bad, except that it prevents the heat from spreading further. You wouldn't want to anneal the necks and leave the cases sitting there hot enough to cause parts of the body or head to also end up annealed. Getting the neck hot enough fast enough and then ending the process in water saves the rest of the case. Rapid cooling has no effect on cartridge brass.

[rantingredneck]

Well then there ya go. Makes sense then.........

[Mike Irwin]

"Quenching the brass in water has no effect on the annealing process, good or bad, except that it prevents the heat from spreading further."

That.

You want the neck and shoulder soft, but the last thing you want is the case body or god forbid the case head soft. That would cause REAL problems.

The quenching in water ensures that the residual heat in the case doesn't move down the case body, and it also allows you to quickly clear the case out of your work area so you can do the next one.

In essence, it's part necessity, part convenience.

[gonzoo75]

all very good information to know. thank you. Another question how many firings before you anneal. And how do you know when you have the case neck to the right tempature.

[Brian Pfleuger]

The number of firings before you anneal depends on several factors, not the least of which is brass brand.


On the topic of "how do you know"... well, that's a real can of worms right there....

There is a product called Tempilaq that will change color at the appropriate temperature. I researched the process pretty thoroughly and came to the conclusion that there was no other reasonable way (apart from building a machine) for the home reloader to anneal brass consistently and safely.

You will soon realize that this topic will start quite an argument and you will have to make up your own mind when all the forth coming arguments have concluded.

[mehavey]

... right temperature...

Use a welder's crayon and/or Tempilaq (that comes in the Hornady annealing kit, which I highly recommend for any number of reasons.)
http://www.midwayusa.com/product/360...nealing-system

See also...

http://www.com/annealing.html

......and...

http://forum.accurateshooter.com/ind...opic=3757882.0

for great description/discussion.

[jepp2]

Another question how many firings before you anneal.

It depends on how much you work the neck. If you run the neck into a normal sizing die each time, it works the brass neck much more than a Lee collet die. This is because the die reduces the neck diameter more than necessary, then the expander opens it back up.

I use the 650 degree temp stick, work great for me. Easy to see it melt, and you know the temperature of the neck has achieved a high enough temperature to anneal. I found this article to be very helpful link

[orionengnr]

Quenching the brass in water has no effect on the annealing process, good or bad, except that it prevents the heat from spreading further.

Not so sure about that. In the 70s I was taught to heat (cherry red) then cool in water (anneal) the copper head gaskets for air-cooled two-stroke motorcycle engines to allow the gasket's re-use. I'm still doing that today.

I'm sure it goes back a good bit farther than that, but I can only attest to it's practice back that far.

[Brian Pfleuger]

I don't know the properties of copper but if it's similar to brass, the heat is the annealing and the water is cooling it off so you can handle it.

I do know in regards to cartridge brass the water portion is only to stop the spreading heat. Some annealing methods don't even use water... the case is simply mounted in a heat sink to protect the head/body.

[deepcore]

I finally broke down and bought a mechanized annealer awhile back.
I used to do the case-in-a-deep-socket-wrench-in-a-drill method and plopped the case in water after annealing.
I recently did a "what would happen" (because the machine enabled repeatability/uniformity) and applied some 450 deg. Tempilaq on the bases of some .308 cases (base to lower third of cases) ran them thru the annealer and did not water quench.
The Tempilaq did not even start to change (waited 30 mins).

[mrawesome22]

I don't know the properties of copper but if it's similar to brass

Brass = 75% copper, 25% zinc.

Don't the brass manufacturers anneal the brass as it sits in water so the heat can't migrate into the body?

[Brian Pfleuger]

I do know that brass is mostly copper, I'm just not sure how the zinc changes it properties. Incidentally, most places list the composition as 70/30.

Originally Posted by mrawesome22

Don't the brass manufacturers anneal the brass as it sits in water so the heat can't migrate into the body?

I'm not too sure about that.... they would have to use a LOT of heat. Brass is an excellent heat conductor and it would be difficult to heat the necks enough if the rest of the case was sitting in water. Anything's possible, but it seems more likely that they use a machine that heats the necks and then drops them into water.

Most companies also tumble the brass after annealing, which is why the stains from the heat are no longer visible. There is at least one company that leaves the stains.... Lapua, maybe? I can't remember.

[4runnerman]

As shown to me. heat brass with 2 torches facing each other (neck only) for 4 seconds,remove from heat,, count to three and drop in water. You can tell if you did it right when you go to chamfer the mouth.

[hornetguy]

I was taught to stand the deprimed cases in about an inch of water to anneal. When the necks achieved the desired "color", you just tip them over into the water. That way, you are assured the bases never get hot.

I haven't annealed any cases in a LONG time, though.

[FrankenMauser]

Most companies also tumble the brass after annealing, which is why the stains from the heat are no longer visible. There is at least one company that leaves the stains.... Lapua, maybe? I can't remember.

Yea. Lapua brass comes deeply "stained" from annealing.

R-P bulk brass will often show the annealing "stains", as well. (They don't seem to finish the brass as well as regular production stuff.)

[mete]

Brass is primarely Cu/Zn and the most ductile is "cartridge brass" ,70Cu-30Zn .Ductility is necessary to form the case.Annealing starts at about 450 F.

[Elkins45]

A reasonably controlled method is to dunk the case mouth and shoulder into a pot of molten bullet casting lead for a controlled count (one one thousand, two one thousand,...) then dunk in water. If you hold the case head in your hand you can feel that it isn't getting too hot.

I find this more controlled and repeatable than the torch method, just make sure you give the case a little flick of the wrist so there's no lead that hardens in the mouth. I load a lot of 257 Wby And I have found that cases last twice as long if I anneal them, since neck spits due to hardening ruin my cases long before head separations become a problem.

Credit is due to either Dean Grinnell or George Monte for this method, I forget which.

[zplinker]

This article tells it about as well as can be done:

http://www.6mmbr.com/

[hounddawg]

I use a deep well socket just big enough so the case slides in and out easily which is chucked up in a battery operated drill spinning at low speed. I turn all the lights off except one small one behind me, then heat the middle of the neck with a small propane torch as it spins until I just start to see a dull red glow then just tilt the drill so the case falls into a bucket of water. The spinning creates a even heat , the socket acts a bit of a heat sink. I read of this technique over at one of the BR sites where they were interviewing one of the worlds top BR shooters and figure if it good enough for a world champ it is plenty good enough for this old hillbilly.