setting up benchsource annealer

[timelinex]

I just started using a benchsource annealer and I'm not sure if I set everything up right.

I put the flames so they are aimed towards right above the neck/shoulder junction. The inside blue blame is around 5/8" away from the center of the spinning piece (so a little less far from the brass itself)

It looks like with this configuration, I need about 2.8 seconds. Is that right?

I put 750 tempilaq on the inside and outside of the neck and 450 on the body. Here is a video of it:


If you can't see much on the youtube video, go here to see a slightly better one:
[video]http://s1133.photobucket.com/user/timelinex/media/20140530_164547_zpsa6e3e342.mp4.html[/video]

It looks like it goes clear, right before the machine takes it out of the flame. Here is apicture of it afterward, as you can see the 450 turns clear above halfway down the body, so thats good.

Here is a picture of a case annealed, without the tempilaq to discolor it:

How does that look? Is that right? I thought there would be a bluer hue to the annealed cases. Am I holding it in the flame too little or too much?

Thanks!

 

[varmint slayer]

What case are you annealing there? Did you put Templaq on the inside of the neck or just the outside?

 

[timelinex]

What case are you annealing there? Did you put Templaq on the inside of the neck or just the outside?

It's a Winchester 308 case. I put the tempilaq on both outside and inside. If you make the video full screen, it should be visible when the inside turns clear.

It seems like everyone else online has their 308 cases in there for atleast 4 seconds!

 

[varmint slayer]

Yeah you will need longer than 2.5 seconds for sure. Try not painting a few cases without Templaq and then dimming the lights or turning them off completely. Then I would set the timer to 4 seconds or so and then watch it go through the torches. Watch for the case neck to turn a maroon color and the flame down stream of the case neck to just start to change from blueish to a orange/yellow flame. You want to time it so that all that is happening right as the brass is being rotated out of the flame. Should looks kinda like this.

 

[timelinex]

Yeah you will need longer than 2.5 seconds for sure. Try not painting a few cases without Templaq and then dimming the lights or turning them off completely. Then I would set the timer to 4 seconds or so and then watch it go through the torches. Watch for the case neck to turn a maroon color and the flame down stream of the case neck to just start to change from blueish to a orange/yellow flame. You want to time it so that all that is happening right as the brass is being rotated out of the flame. Should looks kinda like this.

I'll try doing it visually. Did you watch the video though? The flame did turn yellow/orange, a split second before being rotated out of the flame

 

[varmint slayer]

Yeah I did watch it but the Templaq will do that sometimes pending how much you get on there. Try it without and do the same time you did with the Templaq. I bet you don't see the yellow flame.

 

[timelinex]

OK, so here it is at 2.8 seconds:



Notice how it just starts to turn orange the the flame turns a differnt color just as you said. Here is the result:

If I bump it up to 4.5 seconds which is what alot of people recommend, look the the annealing mark:

It definitely looks like its way too far down the case.

Am I missing something?

 

[varmint slayer]

setting up benchsource annealer

No that's it right there lol. Maybe even a hair faster than that to be honest. My WIN .308 brass takes about 4 seconds with two propane torches but hell it looks like you are there.

That's no Templaq right?

And your not using MAP gas by chance are you lol?

 

[varmint slayer]

Also the pretty blue doesn't always happen. Really clean brass (like SS tumbled) will usually show a good color but the color doesn't always show up.

 

[hdbiker1]

I use the Giraud, which takes about 7-8 sec. because it only uses one torch. My brass shows a definite heat line, but no blue hue like many have shown. But it does give it a different gold color to it. You might try turning your torches down a bit to get the dwell time. Also, I only use the 750 tempilaq on the inside of the case neck.

 

[GIXXER2000]

I also use a bench source. Did you clean the brass first? I use a wet steel media so they come out looking like new. My brass runs for about 3.8 second and has a clear heat line when I do my brass.

 

[timelinex]

I'm using regular propane, not map.

Is it possible my torches are too close? Can you guys tell from the videos if the flame is too close

 

[bubbala]

with the bench source you have a lot of ways to control the heat. i use one torch and a longer time in the fire on 308. and you can turn the torch flame higher.
just seems to suit my rhythm to slow things down.
btw has anyone tried an infer- red thermometer on their cases? i tried a dual laser type and couldn't get it to give a reading.

 

[ZombieMonkey]

Your first case with tempilaq look fine, you don't necessarily have to be worried so much about time as you do the heat. My cases are plenty done at 3.5 seconds with how it's currently setup. I had one batch of 223 cases I did that only needed 3 seconds or so.

Sent from my SGH-T999 using Tapatalk

 

[varmint slayer]

I would turn the torches down a bit and try to get your time a hair longer. Annealing is a function of heat and time. That's why they don't recommend MAP gas because its way to hot and you have no dwell time.

 

[jmorris]

Turn your torches down a bit or move them back some. You don't want the flame to change from blue to orange.

The orange flame is likely the Zinc leaving the alloy, it melts around 787F, likely the temp at the edge when your flame changes to orange.


You want it to look like this video.



The quick and free way to set them up is to start the machine too fast and slow down until your flame begins to change color then speed it back up just enough so it stays blue at the point of index. Once they cool down completely, just run the under annealed cases back through.

 

[timelinex]

I will try turning the torches down.

How are you guys insuring that you set up the flame the same way each time? Or do you do a couple test pieces of brass every session??

 

[Sevo2300]

I keep a couple of sacrificial cases for each headstamp in a bin by the annealer. Seems like I always have to give it a very slight tweak one way or the other. I'm looking to set up the hose/propane tank thing to help minimize some of the variability.

 

[timelinex]

I keep a couple of sacrificial cases for each headstamp in a bin by the annealer. Seems like I always have to give it a very slight tweak one way or the other. I'm looking to set up the hose/propane tank thing to help minimize some of the variability.

Annealing them before doesn't effect how long it takes for them to heat up a second time in a row? (or for that orange flame to start)

 

[ZiaHunter]

Picture of my annealer setup and a little gauge I made to set up the torches. I run mine from a twenty pound tank with a regulator. The regulator provides for a constant flame intensity and is adjustable as well as not having to fiddle with the knobs on the torches. The gauge is a copper 3/8" cap with a nail epoxied to it. I trimmed the nail to a length that I want the tip of the flame to be off the neck by approximately 3/8". I anneal several different calibers and this speeds up setup time and aligns the torches both vertically and horizontally. I was annealing 300 WM cases this evening and it took approximately 6.5 seconds checking with Tempilaq.

 

[SPECR]

Have you thought of just running one torch? It's easier to manage. Besides, the case rotates so two heads is overkill. For 308, I have it set at 4.75 sec for the single heat source.

 

[orkan]

Yeah you will need longer than 2.5 seconds for sure. Try not painting a few cases without Templaq and then dimming the lights or turning them off completely. Then I would set the timer to 4 seconds or so and then watch it go through the torches. Watch for the case neck to turn a maroon color and the flame down stream of the case neck to just start to change from blueish to a orange/yellow flame. You want to time it so that all that is happening right as the brass is being rotated out of the flame. Should looks kinda like this.

Annealing is such an art, rather than science it would seem. However, some things we're certain about, and others we aren't. We have no uber-scientific method to setup, thus we end up sacrificing a few cases during the learning process and at least 1 just about every time we setup our little machines.

When it comes to annealing, I try to keep an open mind, as there are so many different ways to do it, but one thing I'm certain of is that you definitely do not want to see a color change in the flame as pictured above. This is something that I learned the hard way when I was starting out annealing. I ruined a lot of brass following similar advice which said to wait until orange flame. That orange flame color is the zinc being burned out of the brass alloy. Once you reach this point, you have begun ruining your brass. Any time in the heat from then on is just continuing to ruin the brass more. You can burn some zinc out, and still have workable brass, but it certainly isn't the best thing for it. It was made with the composition of metals present in their specific percentages for a reason. Changing those percentages by burning away some of the product is not advisable.

At the onset of every session, I will generally sacrifice one or two cases to ensure I'm setup properly. I will shut off all the lights, and make the room dark as possible. I'll set the timer on the high side and grab my stopwatch. As soon as I see blue flame turn orange like pictured above, I will stop the timer. I subtract at least 0.3-0.5 seconds from that, and then set the timer on the bench source to match. I then run a piece of brass through to check it out. I do some springback testing on it, and inspect it good in the light. If I'm happy, I begin rolling. If not, I tweak slightly.

The "blue" marks you see on people's brass indicates ruined brass if it's present immediately after annealing. The "bluish" tint will show up on its own on properly annealed brass over a long period of time, but you don't want to see it right away.

Same for if you see the brass "glow" in any way, it is not good. If it glows, then you are likely seeing orange flame and you're ruining brass.

Times will vary from brass to brass. Lapua likes a different time than winchester. Thick vs thin, etc. However, the above method of setting up has produced the best results for me over the last 4 years of using my bench source. Once I was sure I discovered this as being the "right" method for me, I sent some annealed brass, some what I thought to be over-annealed brass (orange flame), and some non-annealed brass to a metallurgist friend of mine. At the time he had access to some very expensive laboratory-grade testing equipment, and he was able to confirm that I was annealing as good as he could expect it to be done on the equipment we mortals have access to. He was also able to confirm that my suspicions of the orange flame being bad were correct, in that zinc will burn out of an alloy very easily if care is not taken around an open flame. Burning zinc is a very VERY bad idea, as the fumes created are extremely toxic. Let me be very clear here: If you see an orange flame take off like in the above picture, you are burning zinc, and this is bad.

OP, that "pink" color of your brass at 2.8 seconds is an indication of burned zinc, and this is not desirable. For reference, I'm often at 2.3 or 2.5 seconds for proper annealing on my brass. Though as I said, it varies depending upon the atmosphere (how hot your flames are) and the brass composition/thickness.

 

[hdbiker1]

I was under the impression that zinc had a colorless burn. But I agree that pink case necks tend to be almost a dead soft. But I have fired a few of them in .223 before.

 

[orkan]

I was under the impression that zinc had a colorless burn. But I agree that pink case necks tend to be almost a dead soft. But I have fired a few of them in .223 before.

 

[varmint slayer]

setting up benchsource annealer

Well right or wrong, leaving it in the flame until the flame just turns to yellow as the brass is leaving the flame or even a hair before the change has worked well for me for a lot of brass for quite some time. Never had a situation where the necks were too soft of over pressure issues ect. Worst case is you "sacrifice" a few cases by getting the flame to change to yellow and then turn it down a hair and roll on. I've seen guys go way longer than that and shoot one hole bench rest groups so it can't be hurting that much.

 

[Sevo2300]

timelinex, good question. This method usually gets me withing 1/4 sec of where I need to be (I have multiple headstamps and neck thicknesses) and the time needed doesn't seem to vary a lot between annealing cycles. Maybe there is a difference but it is probably less than +/- .25 sec. I run three sacrificial cases through with Tempilaq and the lights off, and then fine tune with the first few cases.

 

[timelinex]

Thank you all for the great advice. I will back the flame off and test until I see that orange flame, then back off.

 

[orkan]

Well right or wrong, leaving it in the flame until the flame just turns to yellow as the brass is leaving the flame or even a hair before the change has worked well for me for a lot of brass for quite some time. Never had a situation where the necks were too soft of over pressure issues ect. Worst case is you "sacrifice" a few cases by getting the flame to change to yellow and then turn it down a hair and roll on. I've seen guys go way longer than that and shoot one hole bench rest groups so it can't be hurting that much.

If you're fine burning zinc out of your brass because a benchrest guy is doing it... don't let me stop you!

Ask yourself: Why does the flame turn orange?

 

[varmint slayer]

I think if the process was that critical, then we would see and hear about a lot more cases of people having over pressure issues, reduced accuracy ect. I just don't see it making that big of a difference unless you are looking to get like 50 reloads out of your brass. I could be way off but that's how I'm thinking. I'm not trying to argue with you or be confrontational btw. I'm open to hammering details out.

 

[Known]

Hi All,

I noticed in this video linked from the Bench Source site that the flame just starts to turn orange. I'm not saying it's correct or incorrect, but being linked from the Bench Source site I'll bet a lot of folks are using it to set their timing. I know I did:

Bench-Source Case Neck Annealing Machine - YouTube

I have a bench source machine and I noticed that the 750 Tempilaq inside the case neck will melt and disappear about a quarter second before the orange flame appears. I get the orange flame with or without Tempilaq - so it's not the Tempilaq burning off. From now on I'll adjust my time so I don't get the orange flame. Out of curiosity I'm going to see if that timing makes the brass start to glow in a dark room.

On a related topic, here's a thread I started when I noticed that annealed brass is not nearly as soft as factory brass:

http://www.snipershide.com/shooting...175126-annealed-brass-compared-new-brass.html

 

[orkan]

I think if the process was that critical, then we would see and hear about a lot more cases of people having over pressure issues, reduced accuracy ect. I just don't see it making that big of a difference unless you are looking to get like 50 reloads out of your brass. I could be way off but that's how I'm thinking. I'm not trying to argue with you or be confrontational btw. I'm open to hammering details out.

I fail to see the problem here. I do not understand what about this is so difficult to understand. Confrontational or not, it's clear you are resisting the plain facts of the situation. If we are going to do a thing, why not do it all the way right, rather than "almost" right? Why defend doing things "almost" right just because everyone is doing it almost right.

Lets step through this shall we?
1) Flame turns orange = zinc burning. This is fact, and is not disputed by anyone with even a little bit of knowledge in regard to flame testing.

2) Burning the zinc out of brass, turns it to copper, essentially.

3) If copper was the desirable material for cartridge case construction, it would be copper to begin with.

4) Researching how to do annealing is time consuming, and loaded with bullshit, because there is no consensus on what is right vs what is wrong. In my research I saw countless video's of people doing it wrong.

5) The people doing it wrong, don't know they are doing it wrong, because poor accuracy isn't necessarily a direct result of doing it wrong. All kinds of crappy reloading processes still produce acceptable accuracy for lots of people every day. This doesn't mean they know how to anneal brass. It only means they think they know how to anneal brass.

6) You do not need to burn ANY zinc out of the brass, to anneal it properly and completely.

7) You can easily find the spot where the case is annealed properly, and NO zinc is burned out of it, by sacrificing a single case to the orange flame change.

8) So why then, would we recommend that people do the thing that we know is bad, and consider it the right way of doing things?

9) Waiting for orange flame change burns zinc from brass, beginning its transformation into copper, and is not right to be doing to cartridge brass. Period. Sure, as long as you don't burn out ALL the zinc, then it's not going to outright ruin the case. Yet it sure won't be in as good a shape as if it still had all its metals in their original percentages. Sure it's not "critical" to be perfect as you say, but burning zinc from the brass is damn sure not right, and we can EASILY avoid it, so why wouldn't we advocate that instead of advocating intentional negligence into our reloading process?

10) This process of mine was verified by someone I consider to be a whole hell of a lot more talented in metallurgy than anyone I've met. He makes a ridiculous living working for an oil company and can't even really tell me what he works on every day. He's spent his entire life studying metals. I'm inclined to take his word for how to properly anneal brass over most anyone's.

If more people would understand this basic concept, and preach it on the various forums... then others trying to learn how to anneal properly wouldn't have such a hard time of it. I know I would sure have appreciated someone giving me this information about 5 years ago. ... or we can keep preaching how to do it "almost" right. Trying to get 50 reloads out of my brass? Why do we anneal in the first place if not to get as much use out of our brass as possible? Some people may have fun ruining components and wasting time, but I don't. If I can help someone else avoid that by posting this here, then I'm happy to do it. If you don't want to do it all the way right, but just partly right and not get as many firings from your brass, then you're free to do it as you please. I don't think anyone here is trying to stop you from doing what you want. I'm just trying to stop you from telling people to almost do it right when they could be doing it right. These machines make doing it right very easy.

If you try it "my" way, you'll experience all the benefits of annealing, and will get as many firings out of your brass as is possible. If you give the same advice I'm giving, you'll surely help a whole hell of a lot of people save time and effort learning what we've learned.

 

[varmint slayer]

Hmm...

 

[Rangemaster]

I average between 6 to 7 seconds on 308 on up to 300 Wm brass. I start with a low flame and work up the flame so I average the same timing everytime. My brass always comes out with that picture perfect look from annealing.

 

[orkan]

If it isn't zinc that's burning when the flame turns orange, what is it? What else is in brass alloy? Tin? Lead? Why does the brass take on a pink color after this, which is the indication of lack of zinc? (copper)

EVEN IF it's not zinc burning out... something is clearly burning out, or else why would the flame change color? Don't need to be too analytical to realize that something is going on there. Fire generally needs a reason to change color. Hence the existence of "flame testing."

Why do we want to take ANYTHING out of the brass?

 

[varmint slayer]

I don't know what it is but it very well could be zinc lol. Im no expert and i am not going to get worked up about it. All I know is that when you run the brass just like the second video (posted by Known) of the bench source machine running, brass gets softer and all is well for more reloads than ill probably ever get before I loose all the pieces. This is the Internet so take any advise with a grain of salt.

 

[ZiaHunter]

I average between 6 to 7 seconds on 308 on up to 300 Wm brass. I start with a low flame and work up the flame so I average the same timing everytime. My brass always comes out with that picture perfect look from annealing.

Color change in the brass is not always a good indicator that the case is properly annealed. Some brass will change color and some won't even when ran through the machine at the same heat level and time. It depends on the brass and best to sacrifice a few cases using Tempilaq to get it right. I test the cases with different rated Tempilaq to check how the heat is applied to nearly the entire case. I usually do several hundred cases in a run and certainly don't want to find myself in the position of trashing them by over annealing.

 

[waveslayer]

Just use 650 Tempilaq and time it to see how long it takes to burn it... then write the time down. Then use a socket set and turn each brass by hand or a screw gun using your time on a timer

 

[Known]

Hmm...

I went to the link: Flame test - Wikipedia, the free encyclopedia

and it says zinc is Colorless (sometimes reported as bluish-green).

On another site it says zinc "Zinc appears as bright streaks in the flame." Flame Tests

I'm not going to worry too much about this. Orkan and Varmint Slayer both make excellent points. If I find myself without any 750 Tempilaq I'll know to heat the brass until I see orange and back off just a bit until the orange goes away.

Regarding the color of the brass itself after annealing, here's what I have noticed: The color gets deeper if you let if sit for a few days. The type of light (fluorescent v.s. Incandescent) changes the appearance. I can also anneal different lots of Lapua .260 Remington brass (one right after the other) with the same timing and I've noticed slight differences in the color. However, the color is consistent within the lot of brass.

Here's another question for the group: Where to position the flame? The neck? The neck/shoulder junction? Middle of the shoulder?

 

[timelinex]

Ok guys so I did my batch of 1x fired 338 lapua brass. I aimed it at the neck shoulder Junction, made sure to go till the flame turns orange and back off just a little. That actually coincided with when my 750 tempilaq melted. So all seems perfect. The only thing I'm a little worried about is that the annealing color change line, ends about 3/4 of the way down the shoulder, instead of a little below the shoulder. Is this still OK?

 

[orkan]

In regard to flame position, you want it angled as such so that the annealing mark ends up about 1/4 to 1/3 of the way between the shoulder and base. Take a look at lapua brass. That's what I strive toward. Hornady follows suit.

 

[timelinex]

In regard to flame position, you want it angled as such so that the annealing mark ends up about 1/4 to 1/3 of the way between the shoulder and base. Take a look at lapua brass. That's what I strive toward. Hornady follows suit.

Is it OK that this batch ends duo with the mark around the body/shoulder Junction. Next time I'll angle it down more, but I just hope I didn't comprise them!

 

[Rangemaster]

Color change in the brass is not always a good indicator that the case is properly annealed. Some brass will change color and some won't even when ran through the machine at the same heat level and time. It depends on the brass and best to sacrifice a few cases using Tempilaq to get it right. I test the cases with different rated Tempilaq to check how the heat is applied to nearly the entire case. I usually do several hundred cases in a run and certainly don't want to find myself in the position of trashing them by over annealing.

That was what I was referring to, I always work up using tempilaq.

 

[Known]

Is it OK that this batch ends duo with the mark around the body/shoulder Junction. Next time I'll angle it down more, but I just hope I didn't comprise them!

Bench Source recommends the torches remain horizontal. Pointing them down too much will direct heat toward the Bench Source unit. If the video in the first post is representative of your setup, try moving the torches closer instead of pointing them down. It doesn't sound like you compromised anything. For good measure, you can always run them through again.

I heat at the neck shoulder junction and my brass looks like it came fresh from the factory.

 

[Known]

Ok guys so I did my batch of 1x fired 338 lapua brass. I aimed it at the neck shoulder Junction, made sure to go till the flame turns orange and back off just a little. That actually coincided with when my 750 tempilaq melted. So all seems perfect.

Yes indeed - I can't wait to anneal my next batch of brass with similar settings.

 

[timelinex]

Just sized and sat bullets in the annealed 338 brass and wow. Definitely the smoothest and most consistent pressure it's ever been, even more so than new lapua brass.

Thanks for the advice everyone.

 

[orkan]

Glad you got it sorted!

Be sure to share your new-found knowledge, as this subject usually generates as much misinformation as anything I've ever seen.

 

[Larueowner]

1) Flame turns orange = zinc burning. This is fact, and is not disputed by anyone with even a little bit of knowledge in regard to flame testing.

2) Burning the zinc out of brass, turns it to copper, essentially.

I do not have even "a little bit of knowledge in regard to flame testing," but I will dispute that the flame turning orage is zinc burning. I guess I will turn it around, what knowledge do you have and can you provide a scientific source that would support your assertion that the orange flame is infact the zinc burning?

As other's have noted it burns with a blue-green color.

Most blacksmiths know that burning zinc "flares off white zinc oxide smoke and leaves heavy soot like yellow and white oxide deposits where the smoke cools." Zinc Metal Fume Fever : A Case Study : Blacksmithing How-to on anvilfire iForge

Many, with more knowledge about alloys, are clear that burning off the Zinc in Brass happens at much higher temperatures (900C) and typically involves a complex process and electrolysis. Can you remove Zinc from brass? [Archive] - AlloyAvenue network

"When zinc is raised to a high temperature (at or above its boiling point around 900C), it burns and forms zinc oxide smoke." Zinc Safety

Secondarily, my understanding is that Brass is about 20-36%% Zinc.
Source: Cartridge Brass Alloys Revealed by X-Ray Spectrometers « Daily Bulletin

If we are in fact burning off the Zinc, then those areas (neck/shoulder), that burn with an orange flame, would be 20-36% smaller by volume (thinner?) because the Zinc has been burned off.

I am not a Metallurgist, but common sense tells me that with an absence of a white smoke, blue-green flame and a reduction in cartridge size because there is 20-36% loss of mass, I posit that the orange flame for less than a second is not Zinc "Burning."

If you have some scientific support for your assertion, can you share it?

Do not take offence to this message. I too want to make sure that I'm annealing my brass appropriately and not damaging my brass. I'm just looking for a solid scientific foundation to support good annealing practices.

 

[timelinex]

So I've been annealing successfully since I started this thread, however there is one issue I have still been having...

Currently I have 2 extension tubes coming from the torch heads and they connect to 2 small cans of propane. What fixes have you guys came up with to make sure the heat/flame from the torches stay the same.

I've noticed that throughout a batch of brass I find myself having to adjust the timing a couple times.

 

[Boxcar]

A few people have done the single tank conversion with pressure regulator as seen in this thread.
http://www.snipershide.com/shooting...-convert-yours-run-one-10lb-propane-tank.html

Your having to adjust because the smaller tanks lose pressure over time and the output pressure of the gas diminishes.

 

[jmorris]

I do not have even "a little bit of knowledge in regard to flame testing," but I will dispute that the flame turning orage is zinc burning. I guess I will turn it around, what knowledge do you have and can you provide a scientific source that would support your assertion that the orange flame is infact the zinc burning?

As other's have noted it burns with a blue-green color.

Most blacksmiths know that burning zinc "flares off white zinc oxide smoke and leaves heavy soot like yellow and white oxide deposits where the smoke cools." Zinc Metal Fume Fever : A Case Study : Blacksmithing How-to on anvilfire iForge

Many, with more knowledge about alloys, are clear that burning off the Zinc in Brass happens at much higher temperatures (900C) and typically involves a complex process and electrolysis. Can you remove Zinc from brass? [Archive] - AlloyAvenue network

"When zinc is raised to a high temperature (at or above its boiling point around 900C), it burns and forms zinc oxide smoke." Zinc Safety

Secondarily, my understanding is that Brass is about 20-36%% Zinc.
Source: Cartridge Brass Alloys Revealed by X-Ray Spectrometers « Daily Bulletin

If we are in fact burning off the Zinc, then those areas (neck/shoulder), that burn with an orange flame, would be 20-36% smaller by volume (thinner?) because the Zinc has been burned off.

I am not a Metallurgist, but common sense tells me that with an absence of a white smoke, blue-green flame and a reduction in cartridge size because there is 20-36% loss of mass, I posit that the orange flame for less than a second is not Zinc "Burning."

If you have some scientific support for your assertion, can you share it?

Do not take offence to this message. I too want to make sure that I'm annealing my brass appropriately and not damaging my brass. I'm just looking for a solid scientific foundation to support good annealing practices.

The easiest way to know would be to remove the zinc using electrolysis then see if the flame changes color.

We know something changes to cause the flame to change color. I don't think his guess is all that bad, zink melts at 780 deg and the flame color changes right after a 750 deg temp paint on the neck shoulder junction, indicates proper temp has been reached.

Regardless, flame color change is a good (and free) indicator of when you have heated the case beyond what you needed to.

The presence of copper can effect flame color from different elements. If you want to see this for your self place a drinking straw in a flame and note the flame color. Now place the straw inside a copper tube and note the different colors.

I don't think you would see the 20-36% loss of mass for some time, not to mention that the entire case would need to be that hot. Saying that the change in color could not be zinc burning out in less than a second would be like saying a nail couldn't cause a flat tire, because it doesn't happen in one second. Either way air hissing from a tire and the change of flame color are indications of a change in state.

It would be nice to be able to talk with someone that works in a foundry though. The boiling point (much higher than the melting point) of zinc is lower than the melting point of brass. This would lead me to believe that zinc is being vaporized as brass is being created.?