salt bath annealing..does not work ?

I though the typical temp was 700 deg F not the 500-550 used I think I read that a water quench was used- hmmmm rather allowing air cooling( slow cooling rather than a shock treatment) which could possible reverse what is trying to be accomplished- ain't no expert - different materials react differently to heat treatment processes. I have never messed with annealing or tempering brass- steels yes, even cast lead bullets. Course I also realize that they are biased even if a separate lab was used but they set the parameters. Oh well time to add some edumacation on the subject from metalurgy areas rather than equipment mfgs.
 
annealing

Up at Lake City they weren't dropped in water but they annealed them before taper., before they had a shoulder, so I don't know if that made a difference or not. Doug
 
amp report is in C not F. go read again.
blades said:
I though the typical temp was 700 deg F not the 500-550 used I think I read that a water quench was used- hmmmm rather allowing air cooling( slow cooling rather than a shock treatment) which could possible reverse what is trying to be accomplished- ain't no expert - different materials react differently to heat treatment processes. I have never messed with annealing or tempering brass- steels yes, even cast lead bullets. Course I also realize that they are biased even if a separate lab was used but they set the parameters. Oh well time to add some edumacation on the subject from metalurgy areas rather than equipment mfgs.
Click to expand...
 
that would put them at 930 -1030 deg F apx-- over the top temp wise in F, if 700 F is the magic number. so methodology is still suspect. don't know much but I can generally look it up.
 
Interesting article, but it seems to me that if the neck/shoulder is raised to the correct temp for the correct amount of time, it's going to be annealed. It shouldn't matter what type of heat is used. It's just basic metallurgy.

One method or another might be easier to perform, but once a procedure is established, none of them are especially difficult.

I understand they have a product to sell and I hope they are successful with it. I, personally, couldn't bring myself to pay that amount of money to anneal my brass. The salt bath is giving me acceptable results.

Jerry
 
THE 500 C IS FROM THE SALT BATH producer.
so that is what was used in the test

blades said:
that would put them at 930 -1030 deg F apx-- over the top temp wise in F, if 700 F is the magic number. so methodology is still suspect. don't know much but I can generally look it up.
Click to expand...
 
Interesting “study”. I won’t mention any bias, however, temperature is temperature is temperature. Brass needs 800f to be annealed and the salt bath gets it to that temperature. I can’t speak to their brass, but after doing over 1000 rounds of 308 up to 338 edge, I can tell you they soften based on force required to seat, have a consistent feel and shoot consistently after being done.

I’m sure amp, being in competition wouldn’t depict SBA as a farce ..... I still question their conclusion based on basic metallurgy
 
AMP was right! Today I was so bored, I decided to see if the heat from molten salt was actually heat. I stuck my finger in and it didn’t even burn! No wonder AMP said it couldn’t anneal brass.

Disclaimer: The above story is fictitious. Please do not try this.
 
no humor in your post.
amp never said no heat,
they did say the PROCESS did not work, in spite of the high temp.

Mram10 said:
AMP was right! Today I was so bored, I decided to see if the heat from molten salt was actually heat. I stuck my finger in and it didn’t even burn! No wonder AMP said it couldn’t anneal brass.

Disclaimer: The above story is fictitious. Please do not try this.
Click to expand...
 
I've never annealed cases other than the time I put those cases in the oven to dry them out....and ruined them entirely. That episode leaves me thinking that AMP's story is not the whole truth and I can't grasp why they would take the time to write it much less publish it. They've got the better annealer if you can come up with the cash but to say the salt deal doesn't work is kinda pushing it....wrongly pushing it I think.
 
I shot two hundred of mine

last weekend and the rifle did not blow up. I used 700F and they softened up. Look good after they have been fired onest. Now, home and lodd them again for the Firecracker! Tis said they shoot the best on the second loddin. We'll see.

Pete
 
retired said:
no humor in your post.
amp never said no heat,
they did say the PROCESS did not work, in spite of the high temp.
Click to expand...

Come on! It was a little funny. [tough crowd].....
AMP is missing something with their testing. I’ll figure out the math for how many seconds it should take for brass to absorb the 500c and anneal then post the numbers. It is obvious why they wouldn’t want salt annealing to succeed.
 
retired said:
look what AMP has to say
(stirring the pot....lol)
since one missed it already, the amp report is in C,not F

https://www.ampannealing.com/articles/52/salt-bath-annealing--does-it-work-/
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500C is 932F.

550C is 1,022F

Way to hot.

For the most part you can also adjust the salt mixture so it tends to melt at just below the desired temperature.

It is not JUST temperature but time and temperature.

And new brass is hardly a 'gold standard.'

I do not know anyone that would fire new cases in a match.

They usually get a couple firings in the match rifles chamber before they are ready for full precision loads.

An anneal at something around 700F, and then loaded with match loads and tested once more.

My varmint loads do the job with under 1/2 inch at 200 yards on paper.

The 6mmRemAI is slightly better with its heavier bullets than the .22-250AI.

I also use a PID controller to maintain temperature in the melting pot.

The standard lead pot control is a bang-bang thermostat.
The heating is full on or off.
 
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How is it way to hot?? People use 3000f to anneal for a set amount of time. If only dipping the necks for 5-8 seconds, you aren’t over annealing. Temp (500c) is transferred thru the neck almost immediately. They get no where close to melting temp of 1800f. Still not seeing why a high end controller is needed for this. On-off is fine for what we are doing. It is keeping a range not to the degree. KISS principal works fine here.
 
Mram10 said:
How is it way to hot?? People use 3000f to anneal for a set amount of time. If only dipping the necks for 5-8 seconds, you aren’t over annealing. Temp (500c) is transferred thru the neck almost immediately. They get no where close to melting temp of 1800f. Still not seeing why a high end controller is needed for this. On-off is fine for what we are doing. It is keeping a range not to the degree. KISS principal works fine here.
Click to expand...

For the most part you do NOT want the neck annealed to 'dead soft.'

It will not produce adequate neck tension until it has been loaded and fired a few times.

3000F of flame temp is not the same as immersion in salt in terms of heat transfer.

The burning gas is far hotter, but has a far smaller mass.

It is not all that clear if the cases being anneals are de-primed.

The salt heats from both sides when I anneal de-primed cases.

Using a simple bang-bang thermostat always produces a larger swing in the actual temperature.

It would likely take an even more extensive series of test to determine if it produces an actual difference.
The thermostat on my pot failed long ago.
I had a spare PID controller and K thermocouple sitting around.

It worked so well I never bothered fixing the thermostat on the pot.

In stead of arbitrary numbers and experimenting to get a desired temperature I can
fat finger a temperature value into the controller and it gets there very squickly with little overshoot.
 
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Ive used three hundred

of the salt bath annealed cases over the past couple of weeks and they seem NORMAL. I also turned the click of a hundred cases to try and danged if they ain't normal as well :). Life is good.

Pete
 
I have been salt bath annealing .22-250 AI and 6 mm Rem AI for many years.

I have very nice sets of cases that are matched in just about every way.

I even sort them out by neck wall variation before turning them.
The odds are that the case wells follow the neck variation for the most part.

I measured enough to know this was true.

Necks are all 0.0100 thick.
And I turn them, and check with with a 1/10,000 dial indicator.

The usable range on those is not all that large.

Chamber neck is tight enough a non-turned case will not enter.

I have not lost a case to neck cracking in either caliber.
 
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