Prof Young
New member
What does it mean to "anneal" the brass.
Life is good.
Prof Young
Life is good.
Prof Young
What does it mean to "anneal" the brass?
- Thread starter Prof Young
- Start date
Aguila Blanca
Staff
Repetitive "working" of any metal (bending or stretching) tends to work harden it, making it more brittle. This is what leads to cracked mouths and necks in brass. Annealing is heating it up enough to soften it and relieve the work hardening.
That's a loaded question in a reloading forum . Not sure I want to answer . I think AB said it best
That's the answer IMO that best describes what it "means" to anneal a cartridge case . I will stop there as well because there is so much more to "annealing" then just that but in a nut shell that is what annealing "means" in this context .
Bill DeShivs
New member
I would say that annealing is putting a metal into it's softest state.
It seems that the reloaders here only partially anneal, or "temper" their brass.
It seems that the reloaders here only partially anneal, or "temper" their brass.
https://www.dictionary.com/browse/anneal?s=t Brass is a metal that "work hardens" and annealing relieves the stress. Cases are "softer" (just the mouths/necks are annealed), lengthening usable case life. Cracks and splits in the case mouth are eliminated...
"Annealing is heating it up enough to soften it and relieve the work hardening." This says it all. It's also not something you need to do every time. It's only done on an 'as required' basis. Have one bottle necked case mouth(usually) or neck crack, you pitch that one and anneal the rest.
Read this and go buy a propane torch kit and a foil roasting pan.
https://bisonballistics.com/articles/the-science-of-cartridge-brass-annealing
Read this and go buy a propane torch kit and a foil roasting pan.
https://bisonballistics.com/articles/the-science-of-cartridge-brass-annealing
I would put it this way:
For shooting purposes, annealing is the ATTEMPT TO RESTORING the case neck and shoulder to its original tempered condition.
As a center fired case has a range of treatment, we are only interested in the end that fails (neck mostly) through the work hardening process of reloading.
Annealing itself is the art (or science) of heat treatment of metals to get specific characteristics via the use heat.
In our case we are interested in return to a desired condition of a very specif part of the shell case.
For shooting purposes, annealing is the ATTEMPT TO RESTORING the case neck and shoulder to its original tempered condition.
As a center fired case has a range of treatment, we are only interested in the end that fails (neck mostly) through the work hardening process of reloading.
Annealing itself is the art (or science) of heat treatment of metals to get specific characteristics via the use heat.
In our case we are interested in return to a desired condition of a very specif part of the shell case.
hammered54
New member
I miss those days in metal shop.....
Gw44,
That's not annealing, so it's a little OT, but it's good advice for hard brass fired in semi-autos or any other chambers that stretch the head a lot at each firing, so the pressure ring gets very thin. Tossing it lets you avoid head separations. But annealing is concerned with neck splits and shoulder working, so it's a different part of the case. Most brass will reload about a dozen times without neck splits, IME, but if you have a loose chamber neck, it can happen sooner.
At the other extreme, board member Hummer70, a two-time National Palma Match champion, has one .308 Winchester case he's succeeded in loading and firing 150 times. So much more life is possible with careful minimal resizing and periodic neck and shoulder annealing.
Prof Young,
To combine a couple of the previous answers, annealing brass is a reordering of the atomic structure of the metal to remove stresses and, with still more heat, thereafter to go on to lower its tensile strength and hardness.
Fully annealed brass is so soft you can bend it easily with your thumbnail and the necks can be easily bent off-axis when a round goes up the feed ramp. Full softness in the neck and shoulder is just too soft for shooting and is not desirable. What shooters do to anneal case necks is what is called "partial annealing" or "stress relieving" in the copper alloy industry references I've found. It is heating just enough to relieve stress, but no further, as stress relief (reversing work-hardening) is all that is required for the case to continue to withstand reloading operations.
Below is a graph of what happens to the brass at different temperatures over a one-hour soak. Shooters use higher temperatures so it happens faster. As near as I can tell from reading, the rate doubling every 10°C like a chemical reaction applies to stress-relief, and the second image follows that rule to show how much faster stress-relief occurs at higher temperatures. Mind you, this assumes the listed temperatures are reached in the neck and shoulder brass through-and-through.
That's not annealing, so it's a little OT, but it's good advice for hard brass fired in semi-autos or any other chambers that stretch the head a lot at each firing, so the pressure ring gets very thin. Tossing it lets you avoid head separations. But annealing is concerned with neck splits and shoulder working, so it's a different part of the case. Most brass will reload about a dozen times without neck splits, IME, but if you have a loose chamber neck, it can happen sooner.
At the other extreme, board member Hummer70, a two-time National Palma Match champion, has one .308 Winchester case he's succeeded in loading and firing 150 times. So much more life is possible with careful minimal resizing and periodic neck and shoulder annealing.
Prof Young,
To combine a couple of the previous answers, annealing brass is a reordering of the atomic structure of the metal to remove stresses and, with still more heat, thereafter to go on to lower its tensile strength and hardness.
Fully annealed brass is so soft you can bend it easily with your thumbnail and the necks can be easily bent off-axis when a round goes up the feed ramp. Full softness in the neck and shoulder is just too soft for shooting and is not desirable. What shooters do to anneal case necks is what is called "partial annealing" or "stress relieving" in the copper alloy industry references I've found. It is heating just enough to relieve stress, but no further, as stress relief (reversing work-hardening) is all that is required for the case to continue to withstand reloading operations.
Below is a graph of what happens to the brass at different temperatures over a one-hour soak. Shooters use higher temperatures so it happens faster. As near as I can tell from reading, the rate doubling every 10°C like a chemical reaction applies to stress-relief, and the second image follows that rule to show how much faster stress-relief occurs at higher temperatures. Mind you, this assumes the listed temperatures are reached in the neck and shoulder brass through-and-through.
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I swage 9mm junk brass into .40 JHP with a lead core. To soften the brass before I put it into the nose forming die, I take a butane torch and, having placed the 9mm junk brass on nails, will heat the brass until it glows red - then let it air cool.
This removes work hardening and eases up the crystalline structure of the metal and also removes some of the carbon locked in the metal lattice. If you made the brass cherry red and then quenched it quickly in water, locking in carbon, this would harden the brass.
People who do precision rifle round reloading will often anneal the neck of their brass to soften it, thus putting less wear on their case trimmer cutter blade and to make the brass more flexible for bullet seating as well as keeping it flexible so it chambers smoother in their weapon's bore. The softer brass neck is less likely to split as it is flared to accept the bullet and is easier on the crimping die as well.
This removes work hardening and eases up the crystalline structure of the metal and also removes some of the carbon locked in the metal lattice. If you made the brass cherry red and then quenched it quickly in water, locking in carbon, this would harden the brass.
People who do precision rifle round reloading will often anneal the neck of their brass to soften it, thus putting less wear on their case trimmer cutter blade and to make the brass more flexible for bullet seating as well as keeping it flexible so it chambers smoother in their weapon's bore. The softer brass neck is less likely to split as it is flared to accept the bullet and is easier on the crimping die as well.
Well that an interesting take.
Someone who knows will have to weigh in on what hardness pistol brass has at the base. It would be a killer to do that with rifle brass at the base.
There is not any carbon involved with brass, that is a steel process.
Ergo, cherry red and a quench does one thing, permanently softens the brass below its correct condition , ie ruins it.
So does just letting it cool down slowly. No difference as carbon plays no role in this metal.
You anneal rifle brass to return it to its optimal condition for chamber seal and to stop it from cracking the neck after firing.
I will agree that as the cracking starts so does the force needed to seat a bullet so more uniform ala easier bullet seating does result. I have never had one crack inserting a bullet.
Brass splits from firing and work hardening not flaring (which is not oft used other than for lead bullets) - an internal trim removes the need for a flare with flat base bullets and the boat tail takes care of the rest.
On the other hand I have never had a pistol case split, despite the fact I do flare those a bit (mostly use flat base bullets)
I don't do anything for the trim part, I trim when needed, not just after anneal, ergo a trimmer does not care.
Someone who knows will have to weigh in on what hardness pistol brass has at the base. It would be a killer to do that with rifle brass at the base.
There is not any carbon involved with brass, that is a steel process.
Ergo, cherry red and a quench does one thing, permanently softens the brass below its correct condition , ie ruins it.
So does just letting it cool down slowly. No difference as carbon plays no role in this metal.
You anneal rifle brass to return it to its optimal condition for chamber seal and to stop it from cracking the neck after firing.
I will agree that as the cracking starts so does the force needed to seat a bullet so more uniform ala easier bullet seating does result. I have never had one crack inserting a bullet.
Brass splits from firing and work hardening not flaring (which is not oft used other than for lead bullets) - an internal trim removes the need for a flare with flat base bullets and the boat tail takes care of the rest.
On the other hand I have never had a pistol case split, despite the fact I do flare those a bit (mostly use flat base bullets)
I don't do anything for the trim part, I trim when needed, not just after anneal, ergo a trimmer does not care.
Never heard of using heat or quench to harden cartridge brass. Everything I've read says cartridge brass is only hardened by "working" the material. Cartridge cases start out as a soft pellet of brass, and by the time the case is fully formed, the head is adequately hard and the neck and shoulder are too hard. So the neck and shoulder of the case is annealed before it's sold or used to load ammo.
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Grey Lion is wrong about quenching brass. That works with carbon steel and with aluminum that is at just the right temperature but does nothing to harden brass. Indeed many folks anneal in a tray with enough water to keep the heat from the heads and then knock the annealed cases over into the water to cool them for rapid handling, but it doesn't harden them any.
The main thing is the heating red makes brass too soft for neck annealing purposes. That is just in need of partial annealing. If you heat the brass red, you start growing the grains which makes it weaker overall. Case necks annealed that far have to be re-annealed more often than properly annealed cases do, or they start splitting. Figure a good annealing job can last ten reloadings or more, but an overheated case neck can start splitting in just four reloadings or so.
The main thing is the heating red makes brass too soft for neck annealing purposes. That is just in need of partial annealing. If you heat the brass red, you start growing the grains which makes it weaker overall. Case necks annealed that far have to be re-annealed more often than properly annealed cases do, or they start splitting. Figure a good annealing job can last ten reloadings or more, but an overheated case neck can start splitting in just four reloadings or so.
The funny thing is that tipping cases over to cool them faster is not why they do it (or so I think) they think it adds to the process, the infamous quench thing applied all wrong.
The case is going to cool off so fast sitting upright anyway. quite amazing the lack of technical understanding. Seems to be getting worse.
Technically going to red is still annealing, its not the desired temper you want for the neck and shoulder.
How do you determine when its needed?
Some do anneal each time (bench rest types) and while it may not be needed, it does not hurt either. Shaded to the safer side.
On the other hand, you have people like me that can't get a true quality control measure going (one that tells me exactly what temp I have hit) so I under anneal a bit and I anneal more often than a case split, but sooner than a hard to seat bullet.
Per what the experts have weighed in on, if you anneal to 75-80% and do it more often you keep it in the desired range (that is paraphrasing )
So rather than over shoot and wreck good cases, I undershoot a bit and do it more often.
Often there is more than one way to skin a cat (now why anyone would skin cats I don't know other than the local food inspectors did find 7 of them in a Chinese restaurant one time)
The case is going to cool off so fast sitting upright anyway. quite amazing the lack of technical understanding. Seems to be getting worse.
Technically going to red is still annealing, its not the desired temper you want for the neck and shoulder.
How do you determine when its needed?
Some do anneal each time (bench rest types) and while it may not be needed, it does not hurt either. Shaded to the safer side.
On the other hand, you have people like me that can't get a true quality control measure going (one that tells me exactly what temp I have hit) so I under anneal a bit and I anneal more often than a case split, but sooner than a hard to seat bullet.
Per what the experts have weighed in on, if you anneal to 75-80% and do it more often you keep it in the desired range (that is paraphrasing )
So rather than over shoot and wreck good cases, I undershoot a bit and do it more often.
Often there is more than one way to skin a cat (now why anyone would skin cats I don't know other than the local food inspectors did find 7 of them in a Chinese restaurant one time)
LineStretcher
New member
I have a Bench Source Vertex annealing machine. I use 650 degree Tempilac to find the correct amount of time to leave the case neck in the flame. It drops the case into a pan of water so they cool down and you can handle them.
When cases are made, they're annealed several times. The key is to not get them hotter than needed or you risk annealing the head.
You can tell if you need to anneal when you cant fully size the case or if after sizing the case checks ok but within 30 minutes or so it doesnt. Another clue is that you may shave bullets when your seating them.
My Magnum rifle brass seems to work harden after about 3 reloads but I rarely needed to do the non magnums. If a case needs trimming no mater what it is I usually put them aside and when I get enough I'll anneal them and then recheck them and trim.
The cost of my annealer doesnt support the process over just buying new brass but I was intrigued by the process so I bought it and I use it more than I probably need to.
When cases are made, they're annealed several times. The key is to not get them hotter than needed or you risk annealing the head.
You can tell if you need to anneal when you cant fully size the case or if after sizing the case checks ok but within 30 minutes or so it doesnt. Another clue is that you may shave bullets when your seating them.
My Magnum rifle brass seems to work harden after about 3 reloads but I rarely needed to do the non magnums. If a case needs trimming no mater what it is I usually put them aside and when I get enough I'll anneal them and then recheck them and trim.
The cost of my annealer doesnt support the process over just buying new brass but I was intrigued by the process so I bought it and I use it more than I probably need to.