Annealing?

[kilotanker22]

How would one go about Annealing a few hundred pieces of 6.5 creedmoor and 270 wsm brass That I would like to anneal. I have no special equipment. To what temperature must the brass reach? And how slowly must it be cooled in order to anneal them?

[BBarn]

If you just want to soften up the neck and shoulder a bit to extend case life it's pretty simple. If you want a specific softness for consistent bullet pull, a fairly precise method is needed.

I occasionally use a simple method to extend case life. I have a deep well socket fixed up that I can chuck up in a cordless drill. Then I slowly rotate the case while holding the case neck and shoulder area over a propane torch flame for about 5 seconds. Immediately after heating I drop the case into a bucket of water. The rate of cooling has no affect on the final hardness of the annealed area, but dropping it into water ensures no additional heat travels toward the case body and head. You don't ever want to anneal any part of the case body or head.

Annealing a few hundred cases using the simple method above will take some time.

[Unclenick]

Actually, it's the other way around. Very precise annealing maximizes case life, as over-heating weakens the brass and shortens final life, but it doesn't have a great effect on the bullet pull. The thing that determines how much force it takes to seat a bullet is the elastic modulus of the brass, which describes how much pressure is needed to cause a certain percent of stretching of the brass. It is the same for all hardnesses. The only situation in which hardness becomes a significant bullet gripping factor is when the brass is so extremely soft that just stretching far enough to accept the bullet stretches it beyond its elastic limit and moves it past its yield point and into its plastic range. This is why Bryan Litz could not find any statistically significant difference between the performance of brass freshly annealed on the AMP annealer and brass that had 10 reloads without further annealing.


Kilotanker 22,

Brass is not steel. It doesn't respond to quenching one way or another, so how fast it cools has no effect on annealing it.


Some terminology:

What most of us call "annealing" of brass is technically called partial annealing in the brass industry. It is just applying enough heat long enough to stress-relieve the brass.

There isn't a single temperature that is appropriate. You can use a whole range of temperatures, but keep in mind the hotter the temperature the faster you are done. Here's a plot I made of it for stress relieving:

[RC20]

KT: Some pretty extensive threads on annealing so run the search.

I see Unclenick got in between us, listen to him by away and far above the right way.

BBarn has it right in that you can do a quick sort of anneal that way.

Once you remove from the flame, you don't need to dump into water (doesn't hurt) as the heat is gone and it can get to the base area at a temp that makes it an issue.

That said, the tricky part is too much heat and heating the whole case up enough to do that. Any glow of any kind in the dark is too much.

Unfortunate (my view) the only way to be consistent short of Metal Gods rigorous approach is the Induction and that is about $500.

And the Induction (Annie) is a learning curve and quality testing with the heat crayons as well.

Just remember, anyone who says take it to a glow of any kind is flat wrong.

For the most part it only takes the neck and shoulder to so soft it will never reach the right spring back. But you are getting into the ability to take the temper off the base and that is a really bad thing.

I shot some that I over annealed and base was ok, they were not bad, more in the 1 inch MOA and no spring back anymore.

I didn't get neck splits so it extended life in a way but not what I was after overall.

[Bill DeShivs]

Or, you can use the ultra-scientific method that has worked for over 100 years-
Stand the cases primer-side down in a pan with water covering the rear 1/3 of the case. Heat the case to dull red with a propane torch.
You can not overheat the case heads this way.

[kilotanker22]

So I don't want to anneal the case body or head. So then I wouldn't be able to anneal them in an oven all at once.

[Unclenick]

Bill,

I hate to disagree, but I find red-heated cases usually have to be done again in three to five reloadings or they start to split. Not overdone, they'll usually go 10 or more. Even in a dark room, red is over 950°F. But YMMV.


Kilotanker22,

NO OVENS! Heads are kept hard to give the brass the tensile strength it needs to seal the chamber without blowing out. I've seen photos of stocks, magazines and bolt faces blown completely to pieces from the kind of head failure soften the heads would cause. Even if it didn't blow out, the head will stretch, making the primer pocket so loose you can't seat a primer in it again, so the case will become unusable after firing if it is that soft. If you value your body parts, don't be tempted to try the oven.

Take a look at this picture of a case. The dark area on the neck and shoulder are the only parts that were annealed.

[RC20]

KT: To add in a bit, if you put the case in an oven, the whole case gets heated up the same and you do not in any way want to affect the base.

Theoretically if you put in water AND circulated cool fresh water all the time, you could accomplish that. It would take a heck of a fancy setup though.

Torches can and do work but as note GLOW IS BAD - VERY VERY BAD (Bill D)

There are various temp pastes and crayons you can use to assist this all.

But a consistent torch operation require consistent gas, same time in flame, same rotation of the case in the flame (which is what the more sophisticated annlears do)

Even Induction has its challenges. A buy byJeep Hammer suggested opening the gap up which I did and that helped lower the critical time aspect.

I also use temp sensivive crayones and work up to 750 degree and no higher.

In reality what I am doing is a partial anneal to a partial anneal.

I don't get full benefit, but I do it often enough I stay out of the split neck zone (have not had one since I started)

As the induction nit runs for a bit it also puts out a bit more so you can't go by the first cases either.

If the color appearance does not polish off, you have gone too far. At most I get a light flash of color change.

I also cross check in the dark looking down inside the case to be sure its not glowing.

People like Bill D not only fool themselves but they pass it on that they are doing anneal right and as long as they don't get to the base with the heat all it does is make inferior cases.

[LineStretcher]

RC20 and Unclenick are spot on. I have a fancy bench top annealer that uses two propane torches and rotates the case in a carousel. It has a timer that determines how long the case stays in the flame. Basically it's the same as using the drill motor socket technique just a little easier.

I use Templac and not crayons but you can use either. My first case is my test case and I put 750 degree Templac on the neck and shoulder area. I also use 450 degree Templac and put it lower on the case. My 750 is yellow and when it turns brown I stop heating and then drop it in water to cool. When it's cool, I check it to make sure that the 450 degree Templac did not turn brown and if it didn't then I know I have my flame and time in flame set correctly.

I can do a case about every 5 seconds so I think it was a worthwhile expense. I anneal often because if I do it right it doesn't hurt anything and makes just about every other process easier.

[Metal god]

I'm debating if I want to get in on this . I have pictures even !

Using the machines are best but using Tempilaq a temp indicator 750* inside the neck or 450* below the shoulder and a propane torch spinning in a socket and drill works good for small batches


You'll likely want the flame just a tad lower then this . but I had it higher to avoid the flame being directly applied to the temp indicator .


Note the 450* temp indicator has melted and there is NO RED glowing brass . If I remember right the brass starts glowing red somewhere around 900*+ which is to hot for cartridge brass . FWIW you can't tell if the case reached the right temp by observing anneal marks either . The test I've done have shown how hot the flame is and where it's applied to the case has a great effect on what your anneal marks look like and not what temp the case reached . Which is also shown in the pic above . The case has reached the proper temp and there are no anneal marks .

[Bill DeShivs]

Well, old Bill D doesn't even reload!
But, what Bill D DOES is work with a whole bunch of metal- forming, melting, casting, annealing, etc. I work with brass every day.
If you anneal brass it becomes soft. When you work brass, it work-hardens.
If the brass work hardens enough, it becomes brittle and it splits or cracks.
Resizing brass causes it to work harden- so after a few reloadings, it needs to be annealed.
Now- maybe you guys "partially anneal" brass so that the case neck is springy enough to hold a bullet-I don't know about that. But- i do know that fully annealed brass will take longer to work harden than partially annealed brass.
So- someone explain to me why full annealing the case necks is bad, or why dull red is too hot. You anneal to soften the case and prevent splits.
BTW- any color change in brass from heating can ALWAYS be polished off. It's surface oxidation, and it doesn't go through the metal.
So- before you get all smarmy with me, let's discuss this. I know this eats at all the guys who bought induction annealers, or put cases in sockets- but torch annealing in a pan of water worked well for a hundred years, and I sure would like to understand why doing it any other way is significantly better.

[LineStretcher]

So- someone explain to me why full annealing the case necks is bad, or why dull red is too hot. You anneal to soften the case and prevent splits.

Bill, we try not to exceed 750 degrees at the neck/shoulder area so we don't inadvertently soften the much thicker brass at the base. If that were to occur you may experience stretch and possible case separation. We've found over time that 650-700 degrees is all that is needed to soften 70/30 brass enough for continued forming. I use 750 degree templac and when it turns from yellow to brown just below the shoulder I know I'm at approximately the correct temp.

[T. O'Heir]

Why do you think they need annealing?
Annealing isn't something you do on a regular basis. It's only required when you get one cracked case neck. Then you pitch that one and anneal the rest.
The "special equipment" consists of a regular propane torch and a pan of plain tap water. Cases go into the water up to just below the shoulder. Then you heat 'em until the brass visually changes colour and tip 'em over.
Not red hot or any red. Red hot is too hot and the cases are ruined. Too soft.

[LineStretcher]

Originally Posted by T. O'Heir

Why do you think they need annealing?
Annealing isn't something you do on a regular basis. It's only required when you get one cracked case neck. Then you pitch that one and anneal the rest.
The "special equipment" consists of a regular propane torch and a pan of plain tap water. Cases go into the water up to just below the shoulder. Then you heat 'em until the brass visually changes colour and tip 'em over.
Not red hot or any red. Red hot is too hot and the cases are ruined. Too soft.

What good does it do to anneal a case that's cracked... Ignored...

[Bill DeShivs]

Why "too soft?" Brass can then be worked until it again needs annealing.
It seems like people are over thinking a very simple process.

[BBarn]

Using the cases in a pan of water and propane torch method can achieve the same results I'm getting with the case in a rotating socket and propane torch method. I just find the case in the socket method very easy. I don't care whether the brass is partially or fully annealed. I'm just looking to reduce case splits, and either of those methods seems to have proven itself up to that task.

[RC20]

Well, old Bill D doesn't even reload!

And you are commenting and encouraging someone to do a lethal practice with a contained explosion? Did you even read what Unclenick wrote?

Why do you think your hot water heater has a SAFETY RELEASE on it? By advocating softening up the case, what you have done is plugged the safety relive, cranked up the heat all the way (and walked away) and let her rip (said 55 gallons of water is capable of blowing out a full size classroom, I saw the gruesome pictures - it had kinds in it)

Rifle cases are NOT JUST BRASS.

They are a carefully formed and heat treated brass.

The head of the case is both THICKER and its HEAT TREATED so its not SOFT. You do not want SOFT.

If you work with metals you should know that.

People then pick up on it, pass it along and please read Unclenicks comments about the carnage that will result.

While I have no idea what the base cause was, I saw the results of a blown up rifle (which you are encouraging someone to do) , the shooter was lucky to only loose 5 teeth. The bystander to the left hit by shrapnel was lucky it was a glancing blow.

The bystander on the other side was lucky the shard that embedded itself in the wall missed him (edge on) flesh would have been cut. Eye? Carotid artery? Skull?

[Bill DeShivs]

And, you're talking about water heaters to someone who has been a licensed steam engineer since 1974!

I said nothing about annealing case heads. Read it again. You can not anneal a case head that is sitting in a pan of water! And, case heads are specifically NOT heat treated. The only heat treatment that can be done to brass is softening. Case heads are hardened through work hardening.

So, before you accuse me of something dangerous, learn to read and comprehend what I wrote. While I don't reload, I'm darned familiar with guns, ammunition, and reloading-since I probably have been dealing with them since before you were born.

[RC20]

My apologies, you did say pan of water. I got carried way and I stand corrected.

You did say red hot. That takes all the temper out of a brass case and that brass case is tempered one end to the other with varying degrees of hard to soft but none of it is toally soft.

Once fully soft it can never be restored.

The neck and shoulder are not dead soft and dead soft wrecks the case.

I would think a master cutler would know about temper?

You might want to consider when I was born as I am no spring chicken (grin)

[Bill DeShivs]

OK- let's try this a different way.

If cases are partially submerged in water while heating- it is IMPOSSIBLE to overheat the bases.
People have been annealing case necks in this manner for 100+ years. It works.

Now, explain to me why full annealing of case necks is not desirable, or how it ruins the cases. The first time you resize the annealed brass, the neck begins to work harden again.

[Bill DeShivs]

RC20-

Why do you think fully soft brass can not be restored? Of course it can. The case was fully soft before it was ever drawn during manufacture.

I know quite a bit about "temper." Apparently, you don't.
As I said above- the first time the case is resized, it begins to work harden.

I really would like someone to logically explain this to me. Obviously, you aren't the one.

[RC20]

Maybe not. I have to go with what I have been told on this one (same thing if I was setting off a nuclear bomb , sure I can drop it, but do I know what makes it go boomb in other than a general way?)

So, in this case we are now talking bout neck and shoulder as you wrote it was in a pan of water and that will not mess with that (I did acknowledge that - maybe a bit annoyed still and that is understood. )

You overheat it and you take that very specific temper completely out of that end of the case and its just soft brass that no longer works right.

No matter how much you shoot it its not going back.

You can melt it down and start over again, but you cannot get the temper back to what it was by any method available to a reloader.

Hope that helps.

[kilotanker22]

Here is an article that I found to be helpful and a good read.

http://www.6mmbr.com/annealing.html

[kilotanker22]

I understand why a cartridge case needs to be softer in some places and hard in others. Its really not too complicated.

I believe that I can set something up to anneal cases. Maybe I will buy a Lee Lead pot and the appropriate controls and use a salt bath annealing technique.

Although I do feel like I would prefer using a flame. If I can Buy an annealing machine cheaper than building one I may just do that.

[RC20]

Generally pretty good.

Notice the target shooter at the end goes for maroon color.

That is too hot but he shoots well apparently with those results.

Maybe the anneal every time is a factor?

I went with the Annie it was more straight forward without the extra quality control someone like Metal God puts into it.

I don't mind brass prep, but I reload to shoot more, I want to spend as little time as I can (and have quality reloads) so the Annie works for me.

Others like the torch but to do it truly right is not a slam dunk easy.