PID controlled Salt Bath Annealing- How TO & Results

[sabrecross]

Intro & background:

I completed my build and salt bath annealing system and I want to share it for those of you who are interested in it. I did an enormous amount of research before I decided on this method and my goal was to have a dummy-proof set-up where I could spend the least amount of time possible annealing my brass.

I use to Cast Boolits so I am familiar with PID Controllers and Lee pots.

I have a couple of videos I took illustrating my set-up and annealing virgin Norma 7mm RM brass. I'll include a list of items I used to build the PID Temperature controller, the Lee pot, and the low temperature salts. With the proper safeties in place, this can be a economical way to anneal brass. For me, the proof is in the pudding. I used Tempilaq 750* on my 20 or so pieces of test brass before going for it and I annealed 100 BRAND NEW virgin pieces of Norma brass @ 1.25 each!

And a note, it is 32* outside today and the PID has no problem maintaining the temperature.


Lee Precision Reloading Precision Lead Melting Pot 90021- https://www.ebay.com/itm/Lee-Precision-Reloading-Precision-Lead-Melting-Pot-90021/233058679208?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

Top plate and shell holder- I used some 1/8" steel plate that I had in a scrap pile, the bottom part of the plate that is in direct contact with the salt solution is bare metal. For the shell holder, I used some scrap pieces of brass that I had from a plumbing project. YOU DO NOT WANT TO USE ALUMINUM, the salts will eat it.

PID Build-
https://www.auberins.com/index.php?main_page=product_info&cPath=1&products_id=3
https://www.auberins.com/index.php?main_page=product_info&cPath=2_30&products_id=9
https://www.auberins.com/index.php?main_page=product_info&cPath=7_33&products_id=606
Ball Bearing PC Computer Case Cooling Fan120x120x25mm AC 115V Metal link depot
https://www.auberins.com/index.php?main_page=product_info&cPath=61_63&products_id=274
High Performance Silver Thermal Grease CPU Heatsink Compound Paste Syringe
Heatsink heat sink for a 25A SSR Solid State Relay
Temp Thermocouple K type, stainless Steel Probe, 2m (6.5ft), teflon sealed
https://www.ebay.com/itm/AC-Distrib...=item26102a2f45:g:UikAAOSwBPRcDzH2:rk:42:pf:0
I used a 500w computer power supply (stripped) that already had a male power socket and a power switch. If you use a different enclosure, you will need a power switch and male power socket. I used 14-18 gauge wire to wire everything and I also used wire connectors that I had already. At a later time, I can include a wiring schematic but I'll have to create that because I modified my last PID build. I have the 100V fan wired directly to the Solid State Relay (SSR) so that the fan only comes on when the SSR is running. It is not hard to build the PID...even a caveman can do it!

Salts-
Low Temperature Salts for Heat Treating Quick Temper 275 by Hubbard-Hall
I ordered 3 lbs due to the high shipping charges http://www.hightemptools.com/salts.html

Metronome- I downloaded a basic metronome to my phone so I can be precise on inserting and taking out the brass. I set it to 50 beats per minute and my brass calls for 8 seconds @ 943* F. YMMV...

I think that is everything...

VIDEOS:




Pictures:

 

[918v]

You ruined that brass

 

[spife7980]

You ruined that brass

Why do you say that?

 

[Mordamer]

You ruined that brass

Why would you say that? Looks great to me.

 

[Milo 2.5]

In all our quests to simplify our processes, and the tech to do just that, this seems draconian.

 

[Threadcutter308]

When the PID Controller is set up properly, it will provide extremely consistent temperature of the salt bath. With a non PID control, the faster you go, the more the temp of the bath drops and the longer you have to wait for the temp to come back up and stabilize. This setup greatly reduces that, or eliminates that problem altogether.

He did a great job and he’s right it isn’t too terribly difficult to build/set up. Conversely, if a person were looking for something “out of the box”, this probably isn’t for them.

 

[918v]

Why would you say that? Looks great to me.

Looks?

You don’t anneal based on looks.

You don’t dip Tempilaq into a molten liquid. It’s designed to take its temperature from the brass not the liquid.

While the temperature control is excellent, everything else is poor. You might as well be eyeballing the orange glow.

 

[Mordamer]

Looks?

You don’t anneal based on looks.

You don’t dip Tempilaq into a molten liquid. It’s designed to take its temperature from the brass not the liquid.

While the temperature control is excellent, everything else is poor. You might as well be eyeballing the orange glow.

I was talking about his whole system and method looks good. You still have no supporting statement to "You ruined that brass." He absolutely did not ruin that brass. Your statement is incorrect.

 

[918v]

Yes he did. The brass was properly annealed from the manufacturer and he annealed it again. Even if he did not over cook it, the brass was annealed twice without first having been work hardened, therefore it is now overannealed.

You absolutely CAN overanneal brass by maintaining annealing temperature for too long. Annealing is temperature + time.

 

[Mordamer]

Yes he did. The brass was properly annealed from the manufacturer and he annealed it again. Even if he did not over cook it, the brass was annealed twice without first having been work hardened, therefore it is now overannealed.

You absolutely CAN overanneal brass by maintaining annealing temperature for too long. Annealing is temperature + time.

You could run that brass through his process 100 times in a row without firing it and it would be absolutely fine to use after. You apparently know very little about material science. You can't anneal it twice and make it softer if it was fully annealed the first time. The only way you ruin brass casings is by annealing the case head. He did not anneal the case head, so he is good to go. The brass probably did not need to be annealed since it was virgin and had most certainly been annealed after being stamped, but he didn't hurt it by annealing it again. These myths about over annealing case necks and shoulders need to go away. He certainly didn't over anneal at 8 seconds in 900 degree Fahrenheit salt.

The definition of ruined is "To reduce to a state of irreparable damage or harm." So if you think it is ruined then what are the side effects that you claim he will experience? The brass won't hold a seated bullet? The brass will give horrible accuracy? The brass will give high ES and SD? The brass will explode? The rounds won't go off? If these or other side effects are your claims then try to articulate them to us.

Once again, your statement is incorrect. You are wrong about the brass being ruined. I predict he can obtain excellent precision and velocity variation with that brass if the rest of his reloading procedures are consistent.

 

[sabrecross]

You ruined that brass

Hopefully the weather will cooperate this week and I will be able to shoot. After annealing the brass, I sonic cleaned the brass. I neck-sized them, primed them, added powder, and seated the bullets. The neck tension was consistent and I checked the bullet-runout. It was < .001. If the gun blows up in my face, then you will be correct that I ruined the necks.

I'll be using a Magnetospeed to check the fps, Average fps, SD, and ES. I'll be mounting the magneto from a picatinny rail so it will not affect my groups. I'll report my progress if I'm still alive....lol.

 

[Mordamer]

Hopefully the weather will cooperate this week and I will be able to shoot. After annealing the brass, I sonic cleaned the brass. I neck-sized them, primed them, added powder, and seated the bullets. The neck tension was consistent and I checked the bullet-runout. It was < .001. If the gun blows up in my face, then you will be correct that I ruined the necks.

I'll be using a Magnetospeed to check the fps, Average fps, SD, and ES. I'll be mounting the magneto from a picatinny rail so it will not affect my groups. I'll report my progress if I'm still alive....lol.

Excellent. Some people are just salty because they probably bought a $1300 dollar annealer and bashing your method makes them feel justified with their expenditure.

 

[sabrecross]

Excellent. Some people are just salty because they probably bought a $1300 dollar annealer and bashing your method makes them feel justified with their expenditure.

Thank you, I appreciate it. With one kid in college and one getting ready to gradate high school, I have to pick where I invest my hobby money. I wanted something consistent where I could minimize my errors and I knew the open flame method wouldn't be best for me. Again, I appreciate your feedback.

 

[Badfinger]

I recall a meeting at Toyota in Georgetown KY with Mr. Toyota present. After dinner he was talking to a group of suppliers when he said ”the factory of the future will have two employees.” With everyone intently listening he further stated there will be an engineer and a dog. The engineer’s job will be to feed the dog. The dog’s job is to keep the engineer away from the equipment. He was ahead of his time

 

[spife7980]

I anneal all my factory brass I intend to use for precision (so all of it). With factory it’s a bit like forest gump and you never know what you’re gonna get. Now I know.

Heat migrating to the case head will wreck a case. Temp of the brass way above 1k degrees will ruins case because 1) to get that hot it takes time and time allows the heat to migrate to the case head and 2) after a certain point it does get too hot. But that point is around 1200 degrees if I remember the charts right. The pot never gets over that 934 temp he had and it never will so it’s inlossible for him to have made it too hot. He only had that big mag brass in for 7-8 seconds, not long enough for it to travel very far down the case.

Repeated annealings don’t wreck brass if it’s allowed to completely cool in between. Back to back will because it starts hot and then only gets hotter. The grain structure takes temp to recrystalize. Now, for an hour or so then yeah, lower temps can do the same but for seconds a a time? Nah.

 

[918v]

You could run that brass through his process 100 times in a row without firing it and it would be absolutely fine to use after. You apparently know very little about material science. You can't anneal it twice and make it softer if it was fully annealed the first time. The only way you ruin brass casings is by annealing the case head. He did not anneal the case head, so he is good to go. The brass probably did not need to be annealed since it was virgin and had most certainly been annealed after being stamped, but he didn't hurt it by annealing it again. These myths about over annealing case necks and shoulders need to go away. He certainly didn't over anneal at 8 seconds in 900 degree Fahrenheit salt.

The definition of ruined is "To reduce to a state of irreparable damage or harm." So if you think it is ruined then what are the side effects that you claim he will experience? The brass won't hold a seated bullet? The brass will give horrible accuracy? The brass will give high ES and SD? The brass will explode? The rounds won't go off? If these or other side effects are your claims then try to articulate them to us.

Once again, your statement is incorrect. You are wrong about the brass being ruined. I predict he can obtain excellent precision and velocity variation with that brass if the rest of his reloading procedures are consistent.

You don’t know shit about cartridge brass and how overannealing affects performance.

 

[918v]

I anneal all my factory brass I intend to use for precision (so all of it). With factory it’s a bit like forest gump and you never know what you’re gonna get. Now I know.

Heat migrating to the case head will wreck a case. Temp of the brass way above 1k degrees will ruins case because 1) to get that hot it takes time and time allows the heat to migrate to the case head and 2) after a certain point it does get too hot. But that point is around 1200 degrees if I remember the charts right. The pot never gets over that 934 temp he had and it never will so it’s inlossible for him to have made it too hot. He only had that big mag brass in for 7-8 seconds, not long enough for it to travel very far down the case.

Repeated annealings don’t wreck brass if it’s allowed to completely cool in between. Back to back will because it starts hot and then only gets hotter. The grain structure takes temp to recrystalize. Now, for an hour or so then yeah, lower temps can do the same but for seconds a a time? Nah.

Wrong. Repeated annealings continue to soften brass and eventually it gets too soft. Brass needs to be just right for best performance. Not too hard, not too soft. Brass manufacturers know this and deliver brass set to the correct hardness. After 10 or so reloading cycles you really feel the difference in seating pressure. It takes about that many firings to bring the brass back to usable condition after it is over cooked.

 

[Mordamer]

You don’t know shit about cartridge brass and how overannealing affects performance.

How about you call the guys who make the AMP annealer and ask them if running cartridges twice through their annealer with cooling in between will ruin brass? You don't think I know anything so call the experts on the subject and ask. When they tell you it does not ruin the brass I expect an apology. I know you won't do that, but I thought I would offer at least one route for you to educate your arrogant and ignorant self.

 

[918v]

I have two of their annealers and have been using one since they came out. I imported one of the very first. And I ruined a bunch of brass with it until I got a 650 degree tempilstik and then I ruined a bunch more annealing them after every firing and then wised up and now anneal minimally.

I also have an arbor press with a hydraulic pressure gauge, the ability to control neck tension in .0005” increments, and 25 years of reloading experience telling me how a bullet should feel being seated in a case neck.

I also have a shooting buddy who ruined a bunch of brass by annealing and then annealing again because he didn’t get that nice purdy oxide down the shoulder the first time. He was bewildered why his necks and shoulders collapsed causing his rounds to get stuck in the chamber. And the doubling of group size as well.

With annealing, less is more.

 

[Larry Jones]

Thanks for the great info!

I gotta build one of these units.

The Hubbard Hall website is super informative with tech specs on the salt as well.

 

[sabrecross]

Update: I shot 50 of the salt-bath annealed loaded rounds today. Everything went well. Average velocity was 2877. That's with 66 gr of H1000, CCI BR2, Norma virgin brass, Berger 168 Hunting VLD bullets. Accuracy was great.

I was able to shoot out to 658 yds on a 8" round AR500 plate and a 2/3 IDPA steel silhouette. I had first round hits on both plates at 100, 211, 345, and 426. It took me a couple of shots to hit 526 and 658 yds. Once I adjusted my velocity on Strelok Pro, I was consistently hitting both steel pates at distance.

I plan on annealing after each shooting session.

 

[sabrecross]

I annealed for 6 seconds per case this time around and I'm also annealing two cases per time. The PID is regulating the temperature like a pro. I'm doing a little experimentation on the annealing time. I'll update this I as progress for those that are interested.

 

[jimdog708]

When the PID Controller is set up properly, it will provide extremely consistent temperature of the salt bath. With a non PID control, the faster you go, the more the temp of the bath drops and the longer you have to wait for the temp to come back up and stabilize. This setup greatly reduces that, or eliminates that problem altogether.

He did a great job and he’s right it isn’t too terribly difficult to build/set up. Conversely, if a person were looking for something “out of the box”, this probably isn’t for them.

I’m in process of setting up something like this. I’m going to try using a RCBS Easy Melt Furnace, it has the PID built into it. Not sure how much op has in his price wise, but I bought one of these when they were on sale for $125. I can get 10 lbs of salt from Duda Diesel .com for less than $40 shipping included. 5 lbs each of Potassium Nitrate and Sodium Nitrate. According to this chart (#6) a 60/40 or 50/50 mix will work for this application. http://www.substech.com/dokuwiki/doku.php?id=salt_bath_heat_treatment
The pot on the RCBS is bigger than the Lee pot, so if I did my math right it should take a little less than 5 lbs to fill it. I still need to build a case holder.

 

[sabrecross]

Just an update. Been getting consistent results annealing after each firing for 6 seconds. SD is hanging around a 10. Getting consistent hits at 1010 yds on 2/3rds IDPA steel.

 

[r0tt3n1]

Thanks for telling us of your experiences using this method. I am also using salt bath annealing and would like to put my $0.02 in...
I recommend that you lube the inside of the case necks prior to seating the bullet. The process strips the brass bare bare. The Imperial dry lube convenience pack is what I am now using.
After a recent HP 600yd Prone Match that saw my rifle suddenly start shooting fliers everywhere, my barrel was full of chunks of copper. I think that a bullet had stuck to the inside of the case neck and dragged a big old booger of copper down the barrel! The ammo I had made was about 6 weeks old already (the previous month's Match was cancelled) and I went ahead and used it anyway, wondering the whole time if that was gonna happen....
It also could have been a bad bullet that just shed its jacket, but I am taking no chances anymore. Lubing inside the case neck will not hurt anything, and it makes bullet seating much smoother and more consistent.

 

[sabrecross]

Thanks for telling us of your experiences using this method. I am also using salt bath annealing and would like to put my $0.02 in...
I recommend that you lube the inside of the case necks prior to seating the bullet. The process strips the brass bare bare. The Imperial dry lube convenience pack is what I am now using.
After a recent HP 600yd Prone Match that saw my rifle suddenly start shooting fliers everywhere, my barrel was full of chunks of copper. I think that a bullet had stuck to the inside of the case neck and dragged a big old booger of copper down the barrel! The ammo I had made was about 6 weeks old already (the previous month's Match was cancelled) and I went ahead and used it anyway, wondering the whole time if that was gonna happen....
It also could have been a bad bullet that just shed its jacket, but I am taking no chances anymore. Lubing inside the case neck will not hurt anything, and it makes bullet seating much smoother and more consistent.

I'm doing something similar. I do use the sonic cleaner to remove the salt. But after I trim and size, I remove the excess lube by tumbling the brass in walnut media which coats the neck and provides lubrication before adding primers, powder and seating bullets. I too was a little worried about not having any lubrication between the bullet and the neck.

 

[Deleted member 113831]

Just an update. Been getting consistent results annealing after each firing for 6 seconds. SD is hanging around a 10. Getting consistent hits at 1010 yds on 2/3rds IDPA steel.

But how would it have done if you hadn't ruined that brass?

 

[Kyskeet]

In theory cold work "does" affect the recristalization temp of 70%/30% brass, however in this instance at the levels of percent reduction (cold work) imparted through firing between annealing cycles, the recristalization temp difference would have been negligible and therefore the brass was not ruined.

 

[sabrecross]

But how would it have done if you hadn't ruined that brass?

LOL. I had the local EMS on standby in case I squeezed off that first round and I bit the bid one...almost like being back in combat