Salt Bath Annealing Doesn't Work! by AMP

[BigGrizz]

I'll take a hard pass on the AMP. I'm a practitioner of buy once cry once, but the value isn't there for me.

 

[LongBomber]

as other posters have said, the salt bath must be allowing the hottest temps at the top surface of the bath. Simple solution would be to only submerge the neck and maybe the first .1" of the shoulder.
The other question I had is how did they hold the case in the salt bath? Anything on the case mouth, may act as a heat sink and pull the heat out of that area.
Either way I do think the amp gives the best most repeatable results, but I wouldn't say that salt bath doesn't acheive results either.

 

[J E Custom]

Using the BenchSource, I do not quench. Every case spends the same amount of time in the flame, and they are essentially indistinguishable from another once they are done. If there is any difference in migration of heat it is miniscule, and more importantly not done at temps that would anneal the brass.

I suppose that I could have them drop into water when they leave the BenchSource, but see no need for it.

It is up to the Person as to whether he wants consistently annealed cases or not. Water quenches eliminates one more inconsistency, and with the salt bath process it helps to remove some of the salt.

Quenching stops the process at a given point and prevents uneven annealing. In many forms of working metal to reach the exact hardness/softness, Quenching is critical. It is easy to quench cases and does the best and most consistent job. Why not quench ?

J E CUSTOM

 

[Slick8]

I don't have the time today to read the entire thread but will later. I fear that this is a one sided review from a competitor so it's a bit suspect.

I'm very interested in the Salt Bath system so I'd like to review this more.

If someone with a Salt Bath system would send me a couple of cases, I will test them on a Rockwell Hardness tester and give an evaluation. I'd like a large case, 30 cal or better. One should be fired at least 4x fired and the other freshly annealed in the salt bath.

Thanks,
Craig

 

[Gcan]

From the man himself:

Thanks for reaching out to me. I knew that the folks at AMP were doing some lab tests with the salt bath process but I wasn't expecting such a hack job with the reporting.

I've just had a chance to read it through once, and my first reaction is a little jealousy that they have the ability to do all this lab work that I've always wanted to do, but don't have the resources for. Next comes a feeling of irritation that for the last two years the number one criticism I've faced is the accusation that even the bottom end of my range (450°C) was too hot (from all the people who took the internet-accepted number of 750°F as gospel), now I'm reading an attack that says even my top end of 550° is too cold! Call it proof that you just can't make everyone happy.

I will take some time to read it carefully and formulate a response.
Regards,

Gary Chambers
Ballistic Recreations
Edmonton, Alberta, Canada

Hey Gary. Check this out. This is me trying to buy one of your kits after putting in my shipping info. The $1000 in shipping is geeuuuust a bit much. Probably why you have inventory right now. I see where you say you will provide a personalized shipping quote in a day but your system is asking me to ok a $1099 payment to you right now and then what?; trust you won't keep it. Good and you? Let me know how that works. Id like to try it on my store.

If there is an error on your store in coding or English, perhaps you might fix that.

 

[Mikecr]

why would AMP have suggested this in the second to last paragraph of their report,
"For those reloaders considering getting started on annealing, and who are on a budget, we would recommend a gas flame-based option." ?

I think they're implying that flame is closer to induction than dipping, with the assumption that we actually desire full annealing. But I dip because I do not want full annealing. I want controlled/consistent stress relieving, which is nearly impossible with flame..

 

[LongProng]

To me it's all about confidence. We take the time to eliminate as many variables as possible so that we are confident when pulling the trigger at 1000 yds. What AMP is trying to do is destroy confidence in salt bath annealing. You pay for a study, you get the results you want. Why would AMP even take the time and use resources on this "study?" Because they don't like the trend of people flocking to salt bath. Simple business strategy 101.

 

[John Klingenberg]

Ok...the first thing that pops into my mind is something that I've thought was improper to do regardless the method used...quenching the brass.

I'm no engineer so I've never study any on how metal works technically. But I have heat treated and tempered steel while build a AK receiver. It seems to have worked as there is no wear in the areas I did.

Any way...I wonder if they had let the brass cool naturally, if it would have improved there results. I do mine with a torch and let them cool naturally. The brass fairly hot to touch for long time.

I have read like many of you I'm sure, that the job is done as soon as the heat leaves the piece so it doesn't matter how you cool the brass. But that has never seemed correct in my little brain.

Quenching a ferrous metal hardens it, brass has a whole different spectrum of properties. Stress hardens brass, work hardening, by continually reshaping it. High heat simply realigns the grain structure of the brass and this causes it to soften up. Quenching it doesnt have the same effect on brass as it does other metals.

 

[Lasiter]

More information !!!

http://www.metalmart.com/tools/hardness-conversions/brass/

No doubt that different cartridges need different hardness's for their use. and most re loaders would probably want the case to be on the soft side (MINIMUM), but resizing some cases to soft can lead to other problems.

J E CUSTOM

Has there been any study of just stress relief in the brass depending on the type of case preparation? Tumbling with metal media, soft media, no tumbling? Aging? Low temp baking? All these things can be factors in other metals.

 

[Bob Wright]

I worked in Aerospace manufacturing for my career. Everything in material chemistry was controlled.
This goes for cartridge brass. Before we can effectively do any desired annealing or stress relief you have to eliminate the brass chemistry variable.
And this is where I most concerned. We complain about bad brass from brand "x"
but brand y is the only thing we would use. Why? Work hardening processes from one mfr will vary from another mfr without control as to some established spec or std., like a Federal specification tied to every brass cartridge maker including the brass chemistry, physical dimensions of the slugs, work hardening, inspection standards, etc. etc....
Without a controlled process across the industry, how then can we say there is only one way to "anneal brass" when we have no idea how the brass was processed as alloy, work hardening, annealing, firing and re-annealing?
I just started flame annealing my Nosler brass and I successfully did it as evidence of headspace when fire forming. But did I over or under anneal the work hardening? I have no idea....because of this important variable.

 

[Deputy819]

If someone with a Salt Bath system would send me a couple of cases, I will test them on a Rockwell Hardness tester and give an evaluation.

I'll do it! I've got 2 batches of .338-06 cases (Winchester). Both batches have been fired well over 4 times (primer pockets starting to loosen a little). One batch has NEVER been annealed and the other batch was just Salt Bath Annealed last weekend, BUT already sized and tumbled clean (corn-cob media/anneal marks removed). Would that be sufficient for you? I could always fire one, anneal it and NOT size it?

 

[therifleman556]

That's what i love about this forum. No-one happy enough to take someone else's word for something; we'll test it ourselves thank you!

 

[Old Rooster]

I too bought Mr Chambers Salt Bath Annealing kit and am very happy.
I wondered if it really worked so I did a simple test.I had 20 cases of 30-06 that was too worn to reload and tried a primer pocket uniforming tool to see if it worked so I had extra brass to spare.I used 10 at a time.
I put the Lee pot to at 450 degrees Cel and put the brass in for 5 seconds for 10 cases then put them in water.
On the second 10 I put them in for 10 seconds at a little higher at around 500 cel and took all 20 out of the water bucket and dried them all out and tried to reload(without powder and primers).
The 10 that I put in salt bath for 5 seconds loaded all 150 gr bullets just fine.
The second 10 that stayed in the salt bath for 10 seconds at 500 cel crushed all 10 cases at the neck.
While not scientific it showed that annealing took place on the first 10 cases and too much time in salt bath annealed the cases way too soft for use on the second 10 cases.
I'll stay with Mr Chambers Salt Bath system

 

[Shootin4fun]

That's what i love about this forum. No-one happy enough to take someone else's word for something; we'll test it ourselves thank you!

+1
In my book, all that really matters is measured ES and SD. I've been hand loading for decades, and as dumb as it might sound only learned of annealing in the last year.

My limited tests using the torch method (with the eez "machine") have made 3x fired cases of Lapua 6.5CM go from teens SD to single digit. (Magnetospeed V3) Several times now. New out of the box they were single digit.

But the torch method does require sacrificing some cases to get the right dwell time/temp. It is a bit subjective to say the least. There exists the issue of "to glow or not to glow".

My initial tests with 243 adn 270 are also promising but not conclusive due to small sample size. For some reason, the 6.5CM in both Lapua and Hdy were easier to get to a consistent temp over a consistent length of the case than the other 2.

Well, I have come to look at it as just another excuse to spend more time at my hobbies and profession...which seems to be running tests regardless if it's PHOTOGRAPHY, SHOOTING, or AUDIO/VIDEO ENGINEERING all in pursuit of some holy grail of perfection!
LoL, There are endless debates about 4K vs 8K film scanning and electronic image capture and 10 bit vs 12 bit vs 16bit color depth...or 98KHz vs 192Khz audio sample rates or the difference between speakers costing $3500 vs $6500 vs $50K / pair and I'll refer you to a couple of other forums.