salt bath annealing does not work

[rangerlong]

As the AMP is 10x the cost of the SBA setup, I don’t see this as a ploy to sell more AMP units.
The two are really not competitors.
I think they were doing research to see if they should try to grab a share of the low end annealing market and found out SBA can’t meet their expectations.

 

[whatsupdoc]

You know before this thread got twisted a SH member seemed to want to do some independent testing for our benifit but I guess most missed it.

 

[Sean the Nailer]

You know before this thread got twisted a SH member seemed to want to do some independent testing for our benifit but I guess most missed it.

I hope all is not lost, on that opportunity. I'm still watching the tennis match, from the sidelines. I've my own plans in the works, but certain 'life speedbumps' must be achieved first.

 

[Milo 2.5]

You know before this thread got twisted a SH member seemed to want to do some independent testing for our benifit but I guess most missed it.

Cool, but who or what is stopping it? Threads go sideways all the time, who cares, some are better for it, more fun too.

 

[Rocster]

My bias is for the truth... wherever it leads.. As I have stated..

FACT 1: If you have the best annealing machine on the planet why do you care about redneck salt bath? unless it is a potential threat? So since you built an induction machine at considerable costs and investment and if it happens to be true that Salt Bath annealing[SBA] works.... you're not going to be feeling so great about your investment or position potentially.... if another way takes off and is 10x cheaper.......kind of like polariod waking up one day and realizing that digital photography is gonna kill their market
FACT 2: Brass can be annealed and can be SBA in a commercial application or in a lab, the physics is real and it's possible. There have been many links shared in this debate of manufacturing companies that do anneal brass and by salt bath for certain applications.
FACT 3: It is about the process of how to do it. We don't think they really know what they are doing and secondly, if they did care..bring in a guy that's done it for 10 years and shoots damn good and has low SD/ES with his SBA method. They also did not share in the transparency facture who did it.. their first time? and how many cases were actually testing at this temperature for X amount of time etc. basic testing procedures.
FACT 4: The testing is done by AMP or paid for by AMP so it is biased or there is a conflict of interest. Real Scientific Testing is done in an independent lab under very controlled environments with many controls and tests with none of the parties involved period. AMP wants the tests to show that their product is best.
POINT 1: We only care about 2 results... that are the end results, a)does the resulting groups or precision of the actual real-world shooting with salt bath annealed brass show better results in low SD/ES compared to not using it? and b) is the result that the brass life is extending long compared to not annealing when using the salt bath method. Related to this, there are a lot of folks in this group and many other groups and in shooting communities that have been using the salt bath method for years and have seen it that it has worked for years for them and this itself is anecdotal evidence, though not scientific shows that lots of folks been using it and have personally seen the results. So you're telling us all these people are fooled and in a delusional state?
POINT 2: Finally, calling this process "dangerous" is not being straight up, more so shows a biased view from AMP against Salt Bath Method period. That is because a hot bath kettle yes is potentially dangerous in any place but so is an open flame of propane with a process that can allow you to walk away while your annealing machine can run on its own left unattended to start a fire much easier than salt bath can[you must do it yourself with SBA]. It is interesting that AMP has not tested propane flame annealing to see if it measures up, when it is a proven fact that SBA is used in the manufacturing world because it is superior in stable temperatures and even application of it to the metal being treated. Propane flame is anything but constant and precise in application and heat to the case and there is much more room for error in this process which is why many of us went to SBA besides its efficiency and low costs.

 

[Cascade Hemi]

As the AMP is 10x the cost of the SBA setup, I don’t see this as a ploy to sell more AMP units.
The two are really not competitors.
I think they were doing research to see if they should try to grab a share of the low end annealing market and found out SBA can’t meet their expectations.

That's pretty naive.

 

[rangerlong]

That's pretty naive.

In what way?
Ferrari and Ford both sell sports cars, but not to the same people. Mustang is not a threat to Ferrari’s bottom line.
It doesn’t look like AMP is having trouble moving inventory, even though there are less expensive options out there already that are very good.

Last I checked the entire SBA thing was very much a diy setup. You’re gathering up the parts from various sources and putting it all together.

That’s an opening in the SBA market. If AMP could put out a one stop SBA kit that’s easy and clean for ~$200, they would capture all those guys like me who would spend $200 on an annealing setup, but are never going to spend $1400.

 

[Bradu]

In what way?
Ferrari and Ford both sell sports cars, but not to the same people. Mustang is not a threat to Ferrari’s bottom line.
It doesn’t look like AMP is having trouble moving inventory, even though there are less expensive options out there already that are very good.

Last I checked the entire SBA thing was very much a diy setup. You’re gathering up the parts from various sources and putting it all together.

That’s an opening in the SBA market. If AMP could put out a one stop SBA kit that’s easy and clean for ~$200, they would capture all those guys like me who would spend $200 on an annealing setup, but are never going to spend $1400.

Same thing I was trying to say. I have zero interest in sba setup along with the majority of the people buying an AMP. The people buying an amp want the best system and the most consistent results.

 

[spife7980]

So far we have one side with science to base their beliefs on and on the other side we have people saying they don’t believe the science but refuse to offer any supporting evidence of their own to counter it besides that it possible in industrial scaled applications.

 

[Bradu]

So far we have one side with science to base their beliefs on and on the other side we have people saying they don’t believe the science but refuse to offer any supporting evidence of their own to counter it besides that it possible in industrial scaled applications.

But I noticed a difference ?‍

 

[supercorndogs]

So far we have one side with science to base their beliefs on and on the other side we have people saying they don’t believe the science but refuse to offer any supporting evidence of their own to counter it besides that it possible in industrial scaled applications.

If I know one thing, people who will ignore the science when its right there, don't like being told the truth either.

 

[18Echo]

Speaking of science, 97% of scientists believe man made global warming is real.
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He chuckles as he dips a case into his lee lead pot full of liquid salt.......

 

[biffj]

I guess its a little strange to hear that salt bath is worthless when its been used for annealing and tempering by industry for a couple hundred years. Its the simplest way of maintaining a consistent temperature for both of those processes though molten lead or zinc have also been used for that purpose. I'm guessing though that lead bath annealing might not be so popular with the uneducated masses at this time. Zinc tends to diffuse into the brass creating its own issues so that isn't a real option.

Still haven't seen the science in the article as they aren't really showing the whole picture. Looks more like a media day display.

Frank

 

[rangerlong]

I guess its a little strange to hear that salt bath is worthless when its been used for annealing and tempering by industry for a couple hundred years. Its the simplest way of maintaining a consistent temperature for both of those processes though molten lead or zinc have also been used for that purpose. I'm guessing though that lead bath annealing might not be so popular with the uneducated masses at this time. Zinc tends to diffuse into the brass creating its own issues so that isn't a real option.

Still haven't seen the science in the article as they aren't really showing the whole picture. Looks more like a media day display.

Frank

I believe SBA works on some unspecified material, using some unspecified process, in some unspecified industry.
That doesn’t mean it works for rifle brass in your garage.

However, AMP’s testing doesn’t tell me it’s totally worthless either.
They proved it does soften the brass to some extent.
What I missed in their testing is how consistent was the softening across cases? How consistent is the loaded ammo vs not annealing at all?
If it takes cases of inconsistent hardness, and makes them all consistent to each other, firing after firing, maybe that’s all we need.
Do bullets really care if the necks were “properly annealed” to some spec, or whether the grain structure was changed?
For me the goal is more consistent ammo, relative to doing nothing, because as stated, I’m not buying an AMP anyway.
AMP’s testing just says SBA doesn’t truly anneal the cases. I believe that, but they don’t necessarily say that SBA doesn’t improve your ammo.

 

[memilanuk]

I believe SBA works on some unspecified material, using some unspecified process, in some unspecified industry.
That doesn’t mean it works for rifle brass in your garage.

However, AMP’s testing doesn’t tell me it’s totally worthless either.
They proved it does soften the brass to some extent.

That was kind of my take-away as well.

It works, as is, to some limited degree. Just maybe not quite the way people expected i.e. the annealing of the neck and shoulder does't appear to be uniform.

I think the AMP testing provided some valuable clues as to how to refine the process - maybe adjust the insertion depth so that the case neck is in a hotter region of the bath, if there really is a temperature gradient. Or, as was suggested in another thread on another forum, possibly add some sort of agitation so as to make the temperature more uniform throughout the mix.

Some people asked why AMP didn't change their test mid-stream based on what they saw to make it more effective. In my opinion, that's not their job. They were testing the process as described, out of their own pocket, and provided the results to everyone, for free. I can see why they'd have zero interest in improving a competing process. I'd say it was mighty damn generous of them to do what they did, whether you liked the answer you got or not.

If you want to take those results and refine the SBA method so it works *better*, great. Other people would, as my old man used to say, bitch about being hung with a new rope.

 

[lash]

.... Other people would, as my old man used to say, bitch about being hung with a new rope.

I’m one of those people that would bitch about being hung with a new rope. If for some reason I must be hung, I would prefer that you use an old and somewhat decaying rope. I believe that this is one case wherein I would prefer not to be well hung...if you will.

 

[biffj]

I believe SBA works on some unspecified material, using some unspecified process, in some unspecified industry.
That doesn’t mean it works for rifle brass in your garage.

It isn't like this is some sort of rocket science. Heat is heat and unspecified industries use all kinds. Just because AMP wrote a report doesn't make them any more reliable a source than unspecified industries. As to whether it will work on rifle brass in your garage I'm sure it will depend on how guys actually do the job. As with anything in this industry folks add a lot of voodoo and magic to the equation while not following directions. It creates a wide variety of results which are all "known facts" to those who create them. Metallurgy hasn't changed a lot in the last few thousand years and AMP can't really change it with a simple report.

Frank

 

[Cerwinski]

So the questions I'm sure many other common plebs like myself that don't have 1400 to spend on an AMP and are down in the gutters with torches and drill sockets are:

Am I just wasting my time/propane?
Should I spend my money (100 or so is doable for me) on a SBA setup?

WTF is the truth?

 

[briscoetab]

@Cerwinski here is my opinion and thought on it.

The torch and drill can work fine, it is just difficult to be consistent from case to case in my opinion but if you are careful I guess it will work. I say I guess because no matter how careful I was I could never seem to keep it consistent and would waste 10 cases just getting set up every time to what I “thought” was the correct heat and dwell time but there are a bunch of people that advocate they get single SD’s from this method, so if you believe those people then the method works.

I have not used SBA but the concept of it seems to lend itself to being more consistent than a torch and drill and possibly anything that uses a torch in my opinion. The reason I say it may be more consistent is due to the fact in my personal opinion it is hard to control exactly how much heat the cases get using a torch. The torch is so hot and even having a case slightly out of position can really affect how much heat gets to the case in a set period of time. With SBA it seems to me it would be much easier to control how much heat actually gets into the case compared to the tour he methods. It still seems like you need to be careful to keep the solution at the proper temperature and not add so much brass that it will drop the temp too far. Like I said have only used the AMP and torch methods so only have experience with SBA based on what I have read. Once again many people claim consistently getting single digit SD’s using this method, so if you believe them this method works too.

So what do we know, all of the methods seem to work based on people’s experience. For me I could not get the torch to work and based on videos and other information I was afraid I would not be able to get the consistency I wanted using something like the Benchsource or Giraud. This was not because they are unable to give you the consistency but because I didn’t have the ability to do it with those tools. The AMP on the other hand is for stupid people like me I guess who cannot make the other methods work to get to single SD’s, the AMP can be consistent for everyone and you do not have to have any ability to get it to work right. This appealed to me because basically it is point and click there is no way you can mess it up.

It comes down to if you can make a method work, I didn’t feel I could so I had to go with the most expensive option but the least finicky option. I don’t like putting my money into the AMP when I know I could save so much using something else but if I was going to anneal it was going to have to be the AMP based on my ability to keep everything consistent and that is the method I chose.

 

[wapiti16b]

What would be the result of raising the temperature of the salts to say 6ooC or more and the immersion depth to cover the neck and part of the case shoulder only with more time?
If I'm reading this right the issue is induction vs conduction and time frequency to acheive proper temperature to acheive metalurgical changes in the brass. Is this impossible with SBA?.
I can buy a whole lot of LAPUA brass for $1,400.00 and get by without annealing at all before I drop that much money on an AMP machine that is IMHO over priced!, perhaps something good will come of this controversy and the price of the AMP or a new manufacturer machine will make induction affordable to most. In the meantime I'l just keep ruining my LAPUA brass that is on its eighth reloading using SBA!

 

[briscoetab]

I can buy a whole lot of LAPUA brass for $1,400.00 and get by without annealing at all before I drop that much money on an AMP machine

This was my attitude when I first started annealing (which wasn’t that long ago compared to some people on here probably) but the issue that I was having was confidence and downrange feedback that I was doing it correctly. Yes, I can buy a bunch of brass for what an AMP cost but shooting matches if I run in to a bunch of brass that I annealed improperly or simply was annealed to slightly different neck hardness that effected neck tension then I just blew a bunch of money on that match.

I would say that I have spent close to 1400 dollars to attend a bigger match if you add in travel, hotel and entry fee not to mention time off from work, time spent loading ammo, and all the other time that might go into preparing for a match. I know when I went to heatstroke a couple years ago I had 4 nights of hotel stay, two days off work, 250 entry fee and around 22 hrs travel time round trip. I would say that is probably close to 1400 and if saving a few bucks on annealing would have caused me to blow that match I would have been ticked. Not to say I had any kind of chance on placing in the top 20 or anything like that and I actually had my scope go down (not a cheap scope either, high quality one everyone uses but don’t want to start a scope bashing thread).

I wish I did have confidence in using torch setup or SBA but I don’t when I’m the one using it. For those who do, that is great and you have saved a bunch of money compared to me.

 

[rangerlong]

It isn't like this is some sort of rocket science. Heat is heat and unspecified industries use all kinds. Just because AMP wrote a report doesn't make them any more reliable a source than unspecified industries. As to whether it will work on rifle brass in your garage I'm sure it will depend on how guys actually do the job. As with anything in this industry folks add a lot of voodoo and magic to the equation while not following directions. It creates a wide variety of results which are all "known facts" to those who create them. Metallurgy hasn't changed a lot in the last few thousand years and AMP can't really change it with a simple report.

Frank

What?
How other industries use SBA to anneal aluminum or other materials is irrelevant to how well it works on cartridge brass.
AMP represents the cutting edge of cartridge brass annealing, and I’ve heard no claims that they’re not a reputable company.
Show me an analysis of SBA for cartridge brass that comes from a more reliable source and refutes AMP’s claims.
Show me a cartridge brass manufacturer that uses SBA to anneal their brass.

Metallurgy hasn’t changed much in thousands of years!?
Just a few hundred years ago the best “scientists” were trying to find a way to turn other metals into gold.
Today we have tools and processes to analyze the crystalline structure of metals, even in this century we’re still discovering new elemental metals, and yes, in the last century we have figured out how to turn other metals into gold.

Metallurgy is an ever evolving science with huge discoveries just in the last few decades. Humanity hardly knew everything about metallurgy thousands of years ago.

 

[biffj]

I see....so its fine that industry has been using salt baths to anneal, temper, and otherwise work on all metals.... except for the exalted cartridge brass which has special properties no other metal has. It anneals with heat just like most metals and the proper application of heat will cause the softening regardless of how the heat is applied. This is a fact and not just something made up. Induction heating is just that, heating. By heating the metal whether it be the magical cartridge brass or other simple metals it causes changes in crystalline structure of the metal which affect its hardness, ductility and malleability. Induction heating doesn't change anything else and is not magic. It is controllable and may be more precise for timing but this isn't a function that is as critical as some think. Salt baths heat the metal too and are able to maintain pretty precise temperatures which allows excellent control of the annealing of metal, even the magical cartridge brass.

If there are truly problems with salt bath annealing they are more likely related to the operation of the system rather than the mode. By computerizing the induction system AMP has taken the variables of the operator and removed the likelyhood of screwups. The computer controls the timing and the temp which is probably a good thing. I am not saying the AMP system is no good, only that they are arrogant to say that another system is no good when it has been proven for hundreds of years. I believe their system to be too expensive right now but others will come into that market and prices will come down. Marketing is the key to sale of toys and they are hitting the road hard in that area. They already have a wide range of people arguing over whether gas, electric or solar heat is better just by publishing a puff piece in some obscure location.

Frank

 

[Sheldon N]

The addendum posted by AMP is a really good read.

I'm sure SBA is a viable industrial process for brass. Looking at that industrial link there are salts that can go up to 1000 C working temperature range and we know for sure that will anneal.

Taking AMP's research at face value, my guess would be that the working temperatures of the SBA kits people are using isn't high enough to get the "ideal" response from the brass. That is likely a factor of whether brass responds to annealing better with short duration of excessive temperature or to longer duration lower temperature. AMP says no combination of time/temp with SBA would work, I might clarify that no combination of time/temp in the 500-550C range that they tested would work. I'm sure if you started using salts that were 1000 degrees C you'd see wildly different results, but then you'd have the problem of time being much more critical.

 

[Cascade Hemi]

The addendum posted by AMP is a really good read.

I'm sure SBA is a viable industrial process for brass. Looking at that industrial link there are salts that can go up to 1000 C working temperature range and we know for sure that will anneal.

Taking AMP's research at face value, my guess would be that the working temperatures of the SBA kits people are using isn't high enough to get the "ideal" response from the brass. That is likely a factor of whether brass responds to annealing better with short duration of excessive temperature or to longer duration lower temperature. AMP says no combination of time/temp with SBA would work, I might clarify that no combination of time/temp in the 500-550C range that they tested would work. I'm sure if you started using salts that were 1000 degrees C you'd see wildly different results, but then you'd have the problem of time being much more critical.

SBA, using the commonly available salts, will go up to 590C. 8 seconds at 1050F should be plenty of time to anneal a case neck.

 

[_Windrider_]

You didn't answer the question. Are you suggesting the fairly large body of knowledge surrounding salt bath annealing is fabricated? It's strange that a single publication by an economically invested source is suddenly irrefutable evidence that everyone else is wrong. I'll wait while you answer the original two questions.

I think you are missing the point. The article never denied that the salt bath lowered the hardness. It simply stated that it didn’t lower into the optimal value. You are probably feeling less hard brass, maybe compare to how it feels after using an AMP? I’m just saying that you aren’t wrong in your opinion on salt bath and neither is AMP. They are just saying it doesn’t work because it doesn’t achieve the optimal hardness value that is widely accepted.

 

[_Windrider_]

This is pathetic! Nobody is even trying. Let's make this thread go epic.

Molten Salt Annealing is bullshit snake-oil. The people who do it are poverty stricken rubes who've been taken by a huckster.
It makes the cases LOOK annealed, but they're really just discolored from sodium.

Did @TheGerman write this for you?

 

[_Windrider_]

Speaking of science, 97% of scientists believe man made global warming is real.
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He chuckles as he dips a case into his lee lead pot full of liquid salt.......

Actually they believe climate change is real. Warming and cooling are normal. Man didn’t create climate change but we have certainly exacerbated it.

 

[supercorndogs]

Half the people commenting either skipped reading the article, or can't grasp the nuance of what was laid out. Its not a conspiracy, they test specific parameters, that pertain to a specific manufacturing process. How a brass punch or other product is annealed is irrelevant.

 

[Archwarder]

Here is a link to an another study which is one of only a few available which details the relationship between annealing temperatures and time: Recrystallization Behavior of 70/30 Brass

The interesting thing to note here is that the times are in minutes even up to 550C.
The Article on salt bath annealing does seem to show that annealing is taking place, especially on straight walled cases as it appears to show in the addendum. The emphasis in the article appears to be on where the annealing is taking place when it does happen and that somehow the shape of the case is playing a part in what is going on.

 

[wapiti16b]

ANNIE INDUCTION annealing for less than $500.00 , what are the pros & cons VS AMP? .
One third the price roughly!
What Say You?
Let's get real , if an iduction annealer could be had comparable to AMP for 500 , 600, 700 would it not be a world beater?
1400 is way beyond most of us smelly WalMart people.
After some research between SBA & Induction annealing the salt and melter needed would be more expensive than what I own , but if an induction unit could be had for no more than $500 that would be interesting, no need for programs/per brass manufacturer and case specifications as that could be worked out by the reloader.

 

[ken4570tc in WY]

So the questions I'm sure many other common plebs like myself that don't have 1400 to spend on an AMP and are down in the gutters with torches and drill sockets are:

Am I just wasting my time/propane?
Should I spend my money (100 or so is doable for me) on a SBA setup?

WTF is the truth?

I'm not settled one way or the other yet on the SBA method. My first try didn't give me as good a results as I've had with torch and socket method. SD's for torch and socket in the single digits and high 20's for SBA on 86 pieces of once fired brass. I'm going to try ten at 940F for twelve seconds and ten more for eighteen seconds. It may be a couple of weeks before I can report back on this thread.

 

[918v]

Consider people get single digits SD without annealing at all

 

[Fig]

Yea, but not everyone is willing to anoint their bullets with the menses of a virgin.

 

[whatsupdoc]

Above is same lot lapua brass fired at the same time same load. Starting from the left case 1,2,5,6 are once fired, SBA, FL resized and a mandrel pushed into the neck. Case 3,4,7,8 are virgin with a mandrel pushed into the neck.
You can see that there is soot on the shoulder on the once fired SBA cases where the virgin cases have no shoulder soot.
This leads me to believe that the virgin brass necks are softer than the SBA case necks.






I then grabbed 5 once fired cases that were already processed, they were steel pin tumbled, SBA, FL resized and mandrel pushed into neck and SBA them again. So I basically SBA after sizing. I fired these today, look at the shoulders.

Velocity Results 6mm Creedmoor 41.0 H4350 105 HPBT
3063
3063
3062
3063
3056

Curious if anyone has tested annealing before and after resizing and what were your results.

 

[supercorndogs]

Yes, annealing after sizing does not work well because the dimensions of the brass change. The time I annealed after sizing, most of my brass was hard to chamber.

 

[mdmp5]

So far we have one side with science to base their beliefs on and on the other side we have people saying they don’t believe the science but refuse to offer any supporting evidence of their own to counter it besides that it possible in industrial scaled applications.

Sounds like the democrat party

 

[CaptNemo]

I just SBA’d well I guess I ruined a bunch of brass last night with my “Red Neck” setup...
I hope I don’t die.

 

[supercorndogs]

SBA would have to be able to anneal brass, to be able to over anneal brass, so you are pretty safe.

 

[Cascade Hemi]

SBA would have to be able to anneal brass, to be able to over anneal brass, so you are pretty safe.

This comment made me laugh...well done!

 

[jthor]

I can mount, do grain structure, micro hardness etc.

Have you started this? Just curious.

Google - Induction brass annealer redux
Anyone wanna build me one?

I've built one based off the original design. I vectored from it just because I wanted to automate it among a few other things, but it still uses the same power supplies and induction board. Build one, it doesn't have to be fancy like some of ours have turned out to be, but you certainly will not regret it.

 

[JMcBurn]

Have you started this? Just curious.

I've built one based off the original design. I vectored from it just because I wanted to automate it among a few other things, but it still uses the same power supplies and induction board. Build one, it doesn't have to be fancy like some of ours have turned out to be, but you certainly will not regret it.

Never got any brass to test.

I ended up buying a setup that someone made that they replaced with a bigger one they made. Only played with it so far but it seems like it will do the trick.

 

[jthor]

Never got any brass to test.

Bummer

 

[2aBaC̶a̶]

Brass in one hand fire in the other. How real men anneal their brass.

 

[J McGriddle]

I'm glad you guys told me that SBA doesn't work. Otherwise, I might wonder why my ES isn't lower.

 

[MikeMcCasland]

I'll go against the grain here...

I have an AMP Mk2 and anneal every firing. I've seen literally no change to my SDs after I started annealing with it, and I'm a few thousand rounds in. In fact, the only change I can see from annealing is at the bench (my shoulder bumps are more accurate, and seating feels more consistent). I haven't seen any increases in my X-count.

I find it really interesting everyone comes in here saying their SDs are way better, because that's not been my findings, nor Litz's for that matter (although I take issue with certain parts of his testing).

That said, I'm doing it because the best in my discipline are doing it, and the theory/concept make sense. It also seems to make my brass grow more, which is kind of nice, because it ensures my Giraud will touch the mouth every time.

As far as the insane conspiracy theories about AMP being out to get "the salt bath industry", that's absolute crazy talk. In the article AMP even tells you to buy a flame annealer if you want a lower cost solution.

Here's the deal with AMP...unless you're an absolute moron during the Aztec process, you're guaranteed not to over anneal your brass. You can't really say the same with SBA or Propane setups. With an AMP there's zero guess work, and it's consistent 100% of the time.

 

[Archwarder]

Taken directly from the ASM Materials handbook Vol 4 "Heat Treatment"
(Over 2000 pages on the subject of heat treating and is considered one of the bibles on the subject)

Page 306

Selective tempering techniques are used to soften specific areas of fully hardened parts or to temper areas that were
selectively hardened previously. The purpose of this treatment is to improve the machinability, the toughness, or the
resistance to quench cracking in the selected zone.
Induction and flame tempering are the most commonly used selective techniques because of their controllable local
heating capabilities. The immersion of selected areas in molten salt or molten metal can be accomplished, but with
somewhat less control.

----------------------------

An interesting point to make regarding this book is there is more mention of "Molten salt baths" in the book than "Induction" and "Flame/Furnace" This is due to Molten salt baths being used extensively for controlled "Quenching" of heated parts at a lower temperature.

It does mention using molten salt baths for heating purposes including annealing however it stresses that parts must be fully submerged for an "extended period of time" to ensure enough time is taken for the part to reach the temperature of the bath.

 

[Bradu]

I'll go against the grain here...

I have an AMP Mk2 and anneal every firing. I've seen literally no change to my SDs after I started annealing with it, and I'm a few thousand rounds in. In fact, the only change I can see from annealing is at the bench (my shoulder bumps are more accurate, and seating feels more consistent). I haven't seen any increases in my X-count.

I find it really interesting everyone comes in here saying their SDs are way better, because that's not been my findings, nor Litz's for that matter (although I take issue with certain parts of his testing).

That said, I'm doing it because the best in my discipline are doing it, and the theory/concept make sense. It also seems to make my brass grow more, which is kind of nice, because it ensures my Giraud will touch the mouth every time.

As far as the insane conspiracy theories about AMP being out to get "the salt bath industry", that's absolute crazy talk. In the article AMP even tells you to buy a flame annealer if you want a lower cost solution.

Here's the deal with AMP...unless you're an absolute moron during the Aztec process, you're guaranteed not to over anneal your brass. You can't really say the same with SBA or Propane setups. With an AMP there's zero guess work, and it's consistent 100% of the time.

I use a bench source and see no change in sd's as well. I haven't went and done a true test like Litz but I've loaded enough rounds to say that if it has improved than it is minimal. The consistency of the Amp is what is appealing and I would drop the money on one right now if I had seen a significant improvement.

It's no different than the people going crazy over weighing the powder charge to the kernel on a lab scale. A few tests show it isn't much of an improvement so I will stick with the chargemasters for now. A few guys local to me are going crazy over all this newer shit and trying to get there ammo perfect for prs. I've explained my opinion of it and mentioned how they can't out shoot a random ass load out of there gun in prs match conditions even though the one wants to argue. I laugh because he has about 500 rounds of experience with loading and something other than a hunting rifle. He keeps pissing his money away on gear instead of shooting more thinking that it will make the difference.

 

[Milo 2.5]

I'll go against the grain here...

I have an AMP Mk2 and anneal every firing. I've seen literally no change to my SDs after I started annealing with it, and I'm a few thousand rounds in. In fact, the only change I can see from annealing is at the bench (my shoulder bumps are more accurate, and seating feels more consistent). I haven't seen any increases in my X-count.

I find it really interesting everyone comes in here saying their SDs are way better, because that's not been my findings, nor Litz's for that matter (although I take issue with certain parts of his testing).

I've never made any claims on annealing other than the seating force or neck tension becomes more consistent. I am not positive my AMP Mark 2 anneals the shoulder hard enough for any gains and no means or the will to test it.
But I have to say you do go against the grain. If your shoulder bumps are more accurate, and the seating feels more consistent, and now you can trim each firing making necks the same length also, and you are not seeing any gains in the numbers categories or results downrange, something is wrong. To me, it would seem impossible when you make things more consistent that there are no perceived benefits.

 

[briscoetab]

I've never made any claims on annealing other than the seating force or neck tension becomes more consistent. I am not positive my AMP Mark 2 anneals the shoulder hard enough for any gains and no means or the will to test it.
But I have to say you do go against the grain. If your shoulder bumps are more accurate, and the seating feels more consistent, and now you can trim each firing making necks the same length also, and you are not seeing any gains in the numbers categories or results downrange, something is wrong. To me, it would seem impossible when you make things more consistent that there are no perceived benefits.

Those were my exact thoughts, annealing in itself does nothing to improve actual downrange performance. Annealing is a means to make everything else consistent as it relates to sizing brass. If having more consistency in neck tension and shoulder set back does nothing to improve down range performance, then you might as well not worry about those factors and just crank out ammo. If consistency in neck tension and shoulder set back do not improve the performance of your hand loads then we might as well just be using cheap FL dies, throw out the comparator measuring tools, and all of the other stuff that goes along with keeping sizing of brass consistent.

Annealing is not some sort of magic that improves sd/es. If you do not have a way to already keep brass sizing consistent, annealing will likely do nothing. Annealing just takes the consistency a step further and helps improve brass life in many cases.