Proper flame annealing technique

[TQB]

Hi,

Not being sure if I can get a friend to induction anneal my brass before my next range trip, I am considering using for the first time my flame annealer.

What is the proper technique to flamer anneal? Should I use tempilaq? Were should I apply it? Inside or outside the case neck?

Should I do it as Erik Cortina, having the necks achieve a dull red glow? Or should I avoid glow at all?

Thanks,
Tiago

 

[TQB]

I have used 750ºF and 950ºF tempilaq on the inside of the necks.

With 5 seconds, the 750ºF tempilaq turns black, but the 950ºF remains.
This tells me that it has surpassed 750ºF but has not reached 950ºF.
While it may not achieve proper annealing (95-100 HV), it doesn’t seem to be over annealing.

What do you think?


P.S: some video of the annealing

5 second

8 second

 

[NorCalMikie]

I do simple. Battery powered drill motor. Deep 1/2" socket with adapter to fit the chuck, socket stuffed with steel wool so a case will stick out enough that a flame will hit it. Propane tank sitting on the counter so you're hands free. Case turning in flame for 6 to 8 seconds. I do mine at the kitchen counter with the shutters closed so it's darker and easier to see the case color change. I use MAPP Gas in the torch. Burns hotter so less time in the flame.
Best to try it on an extra piece of junk brass so you can see how it all works. Drop the hot cases in a pan (no water) till they cool off.
It's a "try thing" and it won't take long till you get it figured out. You WILL be an expert. Been doing it for years and STILL havn't had any issues NOT investing in a BIG $$$ annealing machine. Different strokes for different folks. YMMV.

 

[Coyotefurharvester]

I often use a Coleman 1# tank because of the height. 6-9 seconds, turning slowly with the cordless. I angle the flame at the center of the neck toward the case mouth. Cases are tipped out of socket on to a damp cotton towel, on the concrete floor. Lighting low so I can see the slightest red.

 

[darkangel_r2]

If the flame changes color from blue to orange or yellow after it hits the brass (you can see this at the end of the second video) you are burning some material out of the brass. You want to stop just before this happens. A short time of flame change shouldn't hurt the brass.

If you can time the first couple to see how long in the flame it takes for the color to change just set up a stop watch on your phone and put your brass in 1 second less.

Make sure your setup is consistent and puts the neck in the same spot in the flame every time. If your setup moves or you change tanks you should time your brass again.

edit: Orange flame color change may be carbon burning off which doesn't harm brass.

Proper flame annealing technique

The OP was asking for info on tempilaq and dull red case glow when annealing. The only point I was trying to make, was to try and prevent drift with respect to what low temps can do and the difference between some published information that represents bulk and that it is very different than a...

forum.accurateshooter.com

 

[Twicepop]

I have a "circle of fire" type of case annealer. The instructions say to stand the cases in water about 1/2 of the way up to the shoulder. Then point the flame at the neck shoulder junction, when the area of the body below the the neck turns a dull brown knock the cases over in the water to quench. I know the water quench is going to evoke rebuttal. Before driving truck I worked in a large metal forming/forging operation, I was a repair and salvage welder. One of the engineers I worked with (he had masters degrees in mechanical engineering, welding technology and metalurgical sciences) and he "stressed" that brass will harden if heated and allowed to air quench. As a hobby he is an accredited copper smith and builds black powder guns that are works of art as well as functional.

 

[Straightshooter1]

Hi,

Not being sure if I can get a friend to induction anneal my brass before my next range trip, I am considering using for the first time my flame annealer.

What is the proper technique to flamer anneal? Should I use tempilaq? Were should I apply it? Inside or outside the case neck?

Should I do it as Erik Cortina, having the necks achieve a dull red glow? Or should I avoid glow at all?

Thanks,
Tiago

For a few years now I've been flame annealing with an Annealeez and use the "red glow" method (in a dark room, like the videos above). And I've use tempilaq 750 to see how my red glow method was working. And I found it worked quite well.

Using the flame to anneal requires finding the right amount of time a case needs to be in the flame to get to the right temperature. This time can vary depending on the particular case specs as thicker brass will heat up slower than thin brass . . . obviously. And the ambient temperature has some effect too. For example, when I anneal in a cold garage, it takes a little longer to get to that red glow point than it does in a hot summer garage (the brass temperature tending to equalize the ambient temperature. So, I always test for the glow point (usually with some scrap range brass of the same headstamp and dimensions). And when using the red glow method, I make sure the brass starts moving out of the flame the instant the glow begins to appear. So, it only glows for a very short time. This method has been working well for me.

 

[lb-ft]

The very dark room, drill motor, deep well socket, propane or mapp 5-9 sec, watch for case neck to take on dull red glow (not bright red, nor orange, nor yellow), all EXCELLENT advice.

The one thing I add is a metronome app on your smartphone. You’ll quickly find the matching beats per minute cadence that’s a perfect pair to number of seconds in flame for consistent results.

And absolutely, try in on some worn out brass first.

 

[Webster]

I have used 750ºF and 950ºF tempilaq on the inside of the necks.

With 5 seconds, the 750ºF tempilaq turns black, but the 950ºF remains.
This tells me that it has surpassed 750ºF but has not reached 950ºF.
While it may not achieve proper annealing (95-100 HV), it doesn’t seem to be over annealing.

What do you think?


P.S: some video of the annealing

5 second

8 second

I would give it 7 seconds. It probably doesn't matter. Recently I decided I didn't want to see any red. I have over 20 reloads on my brass. Varmint hunting rifle. Groups around .350". I don't care what my neck tension is or trying to hit some hardness.

 

[RegionRat]

I have a "circle of fire" type of case annealer. The instructions say to stand the cases in water about 1/2 of the way up to the shoulder. Then point the flame at the neck shoulder junction, when the area of the body below the the neck turns a dull brown knock the cases over in the water to quench. I know the water quench is going to evoke rebuttal. Before driving truck I worked in a large metal forming/forging operation, I was a repair and salvage welder. One of the engineers I worked with (he had masters degrees in mechanical engineering, welding technology and metalurgical sciences) and he "stressed" that brass will harden if heated and allowed to air quench. As a hobby he is an accredited copper smith and builds black powder guns that are works of art as well as functional.

Sorry, but this is very wrong in terms of quoting your friend.

Cartridge brass is alpha phase and does not harden due to water quench or air cooling.

It is hardened by mechanical work and annealed by being taken well above the recrystallization temperature for enough time to get the grain change.

Cartridge necks are treated differently than pucks or cups, i.e., bulk thickness versus thin section.

 

[divingin]

If you want a ton of research on the subject, I'd suggest going through AMP's "Our Research" section on the AMP website. Specifically, the "Annealing Under the Microscope" articles.

Induction Annealer | The Latest Research | AMP

View the latest articles from AMP Annealing. Get tips and tricks from our R&D. Here we upload articles to provide your the best possible information on innovations in the annealing process.

www.ampannealing.com

Personally, I use an Annealeez machine. I place the flame on the neck/shoulder junction, and adjust speed so the case mouth/neck just begin to glow a bit (either a dark room, or with hands cupped around the case mouth to darken while trying not to incinerate skin) and then increase speed to reduce dwell time a tad (my aim here is to get the timing just short of the brass glowing.) Works out to anywhere from 4 to 6 seconds or so depending on how the flame burns.

This time can vary depending on the particular case specs as thicker brass will heat up faster than thin brass . . . obviously.

Not obvious to me. More material takes more energy to heat to a specific temp, or takes longer to heat up with a specific energy input. Can you explain your reasoning?

 

[Straightshooter1]

Not obvious to me. More material takes more energy to heat to a specific temp, or takes longer to heat up with a specific energy input. Can you explain your reasoning?

. . . old man syndrome. What I typed didn't match what I was thinking (happens more times than I care to admit). I corrected that post, apparently while you were typing this post.

 

[DocCarbon]

If you want a ton of research on the subject, I'd suggest going through AMP's "Our Research" section on the AMP website. Specifically, the "Annealing Under the Microscope" articles.

Induction Annealer | The Latest Research | AMP

View the latest articles from AMP Annealing. Get tips and tricks from our R&D. Here we upload articles to provide your the best possible information on innovations in the annealing process.

www.ampannealing.com

Personally, I use an Annealeez machine. I place the flame on the neck/shoulder junction, and adjust speed so the case mouth/neck just begin to glow a bit (either a dark room, or with hands cupped around the case mouth to darken while trying not to incinerate skin) and then increase speed to reduce dwell time a tad (my aim here is to get the timing just short of the brass glowing.) Works out to anywhere from 4 to 6 seconds or so depending on how the flame burns.




Not obvious to me. More material takes more energy to heat to a specific temp, or takes longer to heat up with a specific energy input. Can you explain your reasoning?

This is directed towards everyone and Not any single individual ;

Perhaps a better method of measurement exist ,such as placing 400-450 Deg. Tempilaq 0.50" up from the cartridge rebate or Belt or a specific spot above the cartridge base ,say at least 0.75" . I DON'T but others have and their annealing is JUST as good as mine .
As I also use one of those machines with variable dwell . I've personally found by directing the flame from the shoulder towards the case mouth a longer dwell may be safely used and rotation is very important perhaps 10-25 RPM . What WE all are doing is simply reducing work hardness ,aka malleability .
There isn't sufficient time available regardless of Temperature for any significant recrystallization .
So the Dull Red color of the shoulder neck junction ,is adequate IMO . Ideally holding the cartridge case's base at 200 Deg. while holding the neck shoulder at 800 Deg. for 30 minutes ,will do it . Practicality for Reloaders prohibits it ,again IMO .

As the below statement verifies .

https://vacaero.com/information-res...rmation-and-annealing-of-cartridge-brass.html

Annealing experiments were conducted on a number of the cold worked specimens. Figures 5a and b show color etched images of the specimens cold reduced 50% and then annealed 30 minutes at 500 and 700°F. No difference in the microstructure is seen in the specimen held 30 minutes at 500°F while a very small amount of recrystallization is observed in the specimen held 30 minutes at 700°F. Figures 6a and b show color images of 50% cold reduced specimens held for 4 and 8 minutes at 800°F while Figures 6c and d show 50% cold reduced specimens held 15 and 30 minutes at 800°F. No change is observed after 4 minutes at 800°F, while a minor amount of recrystallization has occurred after 8 minutes. Holding specimens for 15 and 30 minutes at 800°F revealed partial recrystallization after 15 minutes and full recrystallization after 30 minutes. The grain structure is relatively fine but is not uniform in its distribution.

 

[RegionRat]

This is directed towards everyone and Not any single individual ;

Perhaps a better method of measurement exist ,such as placing 400-450 Deg. Tempilaq 0.50" up from the cartridge rebate or Belt or a specific spot above the cartridge base ,say at least 0.75" . I DON'T but others have and their annealing is JUST as good as mine .
As I also use one of those machines with variable dwell . I've personally found by directing the flame from the shoulder towards the case mouth a longer dwell may be safely used and rotation is very important perhaps 10-25 RPM . What WE all are doing is simply reducing work hardness ,aka malleability .
There isn't sufficient time available regardless of Temperature for any significant recrystallization .
So the Dull Red color of the shoulder neck junction ,is adequate IMO . Ideally holding the cartridge case's base at 200 Deg. while holding the neck shoulder at 800 Deg. for 30 minutes ,will do it . Practicality for Reloaders prohibits it ,again IMO .

As the below statement verifies .

https://vacaero.com/information-res...rmation-and-annealing-of-cartridge-brass.html

Annealing experiments were conducted on a number of the cold worked specimens. Figures 5a and b show color etched images of the specimens cold reduced 50% and then annealed 30 minutes at 500 and 700°F. No difference in the microstructure is seen in the specimen held 30 minutes at 500°F while a very small amount of recrystallization is observed in the specimen held 30 minutes at 700°F. Figures 6a and b show color images of 50% cold reduced specimens held for 4 and 8 minutes at 800°F while Figures 6c and d show 50% cold reduced specimens held 15 and 30 minutes at 800°F. No change is observed after 4 minutes at 800°F, while a minor amount of recrystallization has occurred after 8 minutes. Holding specimens for 15 and 30 minutes at 800°F revealed partial recrystallization after 15 minutes and full recrystallization after 30 minutes. The grain structure is relatively fine but is not uniform in its distribution.

He is wrong when concluding we don’t get recrystallization. He is also oven soaking specimens at times, and sectioning cartridges in others.

Recrystallization in cartridge necks starts as low as 530 F and continues all the way up. It doesn’t have to be uniform or even distributed to be considered the starting of recrystallization, and it certainly doesn’t have to be a completed change. One author selling equipment doesn’t change over a hundred years worth of metallurgy in cartridge making.

We get recrystallization and hardness value changes in seconds at annealing temperatures in cartridge necks, minutes are not part of the vocabulary. His puck samples may appear interesting to him, but they are not similar to cartridge results.

 

[NorCalMikie]

And if there's any doubt about your brass getting annealed, take two cases, one annealed and one not.
Take pliers and squeeze the neck of the un annealed and see/feel how much force it takes to flatten it.
Then do the same thing on the annealed case neck.
You WILL see/feel the difference.

 

[JFrank]

That's what I don't like about annealing.

 

[DocCarbon]

I beg to differ as George Vander Voort is indeed an Expert , however Draw your own conclusions

https://www.diva-portal.org/smash/get/diva2:1237076/FULLTEXT02.pdf

I borrowed this from Snipers Hide ,as a gentleman had already done an excellent analysis ;


1)The biggest myth is that you can easily over anneal cartridge brass. As per the above studies, you can heat brass to 1300 degrees F for 30 minutes and you will NOT ruin the brass. Directly from George Vander Voort, an expert in the field of Metallurgy “"It recrystallizes the grain structure, removes the cold deformation and returns it to the initial annealed condition with full ductility.”" So if 30 minutes at 1300 degrees F does not damage cartridge brass I think it would be pretty difficult to “over anneal” brass in a few seconds. Caveat –- you obviously to not want to anneal the case head or close to the head.

2)You do not burn the zinc out of the brass when it turns red.

3)You can anneal cases many (many) times, without harming them.

4)By properly annealing (and repeated annealing), cases life will be increased (unless overloaded).

5)Like most aspects of reloading consistency is the key. It is easy to anneal brass but more difficult to get all brass annealed to the same grain structure/hardness

6)Water does nothing for the process

Just my opinion based on my research. An I concur his research is correct

 

[jepp2]

Were should I apply it? Inside or outside the case neck?

Just keep in mind, Tempilaq is basically a colored wax substance. If you let the flame directly impinge on the Tempilaq, it will show a temperature the brass didn't reach. You just showed the flame temperature.

I put a thin line on the inside of the case neck. No need to paint the entire inside surface. If the temperature is achieved, the Tempilaq will no longer be the color it was when you applied it.

 

[JFrank]

@DocCarbon Thanks for that excellent post.
Here's my take and i usually get flamed for my current position.
I spend a fair amount of time getting my competition brass neck turned, fire formed and resized just the right amount to chamber freely and not produce clickers through a string of record fire. Then bushing adjustments to ensure consistent small groups on paper at long range. After that i have a separate set of brass that has to match the first set and shoot exactly the same or as close as I can get them so I cant tell one from the other.
I have good strong brass that reacts consistently sizes well with consistent bullet hold.
After many reloadings im developing what I call a brass history that im fairly pleased with no spring back problems , memory seems good etc. so I really have no reason to anneal but if my brass starts to change or react differently I would take a few or maybe 10 cases to anneal and began to compare using a better or worse type of test over time.

 

[TheCZKid]

I'm curious where the temperature of 750 degrees comes from? The only annealing I've done is using a Hornady Anneal Kit, and it comes with Tempilaq rated at 475 degrees. They state to paint a line on the outside, about 1/4" below the the shoulder, then have the brighter blue of the flame hit the center of the neck, with the case in rotating holder about 45 degree angle. Heat center of neck until the Tempilaq turns clear, and drop case in a bucket of water. If it's slightly dark enough I can see the neck turns a dull red, and (depending on the case) a line forms on the body below the shoulder typically in the same timeframe, and I just use the same time, and dark ring indicator, for amount of annealing for that specific case. My stuff ain't fancy, using a drill motor over a vertical Lenk butane torch.
Am I probably doing this right or wrong? I'd think if you painted on the inside of the neck, then have a torch hit the neck, how can you see what's going on inside?