annealing question

[bobcat93]

Jlow -...that was the input I was looking to hear.. So thank you so much for your comment..Guess its time to spend more money ..my wife will see the annealer and say " what the hell is that, and what did it cost"..its not a case trimmer and hard to hide..lol..

 

[aj300mag]

I didn't have a new case to test. My guess it was in the 82-85 HRB (Hardness Rockwell "B" scale) range. Interesting that there is very little hardness loss at 800F for 15 minutes. I'm retired now. No chance to do testing anymore. For all of the heat treated samples at all times and temperatures I saw no change in grain size. This really surprised me. Large pieces of brass that are commercially heat treated are usually one hour at temperature.

What we are doing is called rapid annealing. Rapid annealing is normally done at higher temperature than annealing of larger heavier pieces. This is because it's time and temperature dependent. A higher temperature requires less time. It's difficult to find published literature on flash annealing because every company determines what works with their parts and heat treating equipment. It looks like you have to find a process that you feel is working on your brass and stick with it.

Using a hardness tester to check if brass is annealed is about as precise as reading tea leaves...

The grain structure needs to be checked, and at 800 degrees the grains aren't at the optimum size.

 

[bobcat93]

Ger. Jim....sorry ..yes it does..I just shake it up, and have at it

 

[CatShooter]

Using a hardness tester to check if brass is annealed is about as precise as reading tea leaves...

The grain structure needs to be checked, and at 800 degrees the grains aren't at the optimum size.

I wonder who will be the first to market a grain analyzer kit???

 

[aj300mag]

Using a hardness tester to check if brass is annealed is about as precise as reading tea leaves...

The grain structure needs to be checked, and at 800 degrees the grains aren't at the optimum size.

I wonder who will be the first to market a grain analyzer kit???

I think the brass you use proves it isn't too critical...

 

[jlow]

CatShooter – I don’t think annealing is an all or none thing. So the term over annealed does not necessarily mean the neck and shoulders has to be dead soft. The graph that Webster generated clearly shows this.

To me, the dead soft over annealed is an extreme situation that I don’t think happens unless you really heat the stuff up really red hot.

I think most of us work not in this areas but in between it and no annealing. The question is which area we are working in. If we look at this graph generated by Weber, I think where we want work in is somewhere in that blue box where the heat will reduced the work hardening but where there is not a huge change in hardness if you are slightly off in terms of temperature. What we don’t want to work in is the area highlighted by the red box where slight differences in temperature will cause big changes in hardness.

The way I look at it, we are trying to generate brass with similar hardness. The exact hardness is not real important as long as:

1) Most of the work hardening from reloading and firing is removed.
2) The degree of hardness from brass to brass is similar.
3) The end product is not overly soft.

This to me is best done using a machine for most folks and working in the blue box area will make this happen.

 

[Syncrowave]

If the necks are black.....they are probably in the dead soft condition........useless for ever getting springback again without re-melting the brass and re-drawing.

I agree that "dead soft" is probably best avoided, but wouldn't working the brass (for example repeatedly sizing the necks and then dragging the expander back through) work-harden the brass the same way it was work-hardened in the first place?

My understanding is that annealing – even to a "dead soft"condition – is not irreversible. You can work-harden it and then anneal it and then work-harden it and then anneal it over and over and over and over.

 

[LHSmith]

My understanding is that annealing – even to a "dead soft"condition – is not irreversible. You can work-harden it and then anneal it and then work-harden it and then anneal it over and over and over and over.

Not according to Ken Light and metallurgists. Try overheating a case and work harden it with a pliers.....it acts like lead......you can't get it to split.

 

[bow shot]

bobcat: My answer to your question is: Yes.

I can tell when I size (neck expand or seat in particular) that some of my brass is harder or softer even though I go through the standard pain level to keep the annealing porcess consistne case-to-case.

Laupua 2.5-284 brass
stovetop
750 tempilaq
24 seconds rotating @ 1rps.
angle/attitude kept consistent and precise

It bugs me.

 

[LHSmith]

To me, the dead soft over annealed is an extreme situation that I don’t think happens unless you really heat the stuff up really red hot.

Read Catshooters post.....he "anneals until the neck is red". I already knew the outcome....but I just annealed a case neck until it just turned red........I annealed another case and maintained a red neck for 30 seconds. I did the pliers test......no difference in springback what-so-ever between the two.....nadda springback, zilch. I don't need someones homemade chart or hardness test to learn what works.....the proof is on the target.

 

[dkhunt14]

I totally agree with you Mr. Smith. The proof is in the target. I anneal every firing about 2 to 2 1/2 seconds with Mapp. If I turn the lights out and watch my machine work the necks start to turn red. I can vary the time from 1/2 a second to 8 seconds by flipping dip switches. When I get some time I talked to my buddy about making a video and posting it on here. The machine I use is a little different than what is out there. It works great and you can really control the time. The cases all come out dead nuts even. Matt

 

[CatShooter]

Read Catshooters post.....he "anneals until the neck is red". I already knew the outcome....but I just annealed a I did the pliers test......no difference in springback what-so-ever between the two.....nadda springback, zilch.

All my cases (new or reloaded) spring back just a few thou, whether fired in a chamber or sized in a bushing die.

I love the "Pliers test". I wasted my money on an Ames hardness tester. I shoulda bought a calibrated pair of pliers.

Learn somfin every day!!

 

[Webster]

I think I made a typo in the text of my post. I mentioned 15M at 800F it was 5 Min. I am very experienced at measuring hardness and grain size. It's one of the many things I did for 45 years. For the highest temperature at 5 minutes I did not see any change in grain size. 15 seconds at the lowest temp had the same GS as 5 min at the highest temp. It looks like the higher temperatures are sufficient to get grain growth but it would take longer than 5 min. You need a microscope to do grain size, plus polishing equipment and chemicals.

Forget about determining hardness with a portable tester. They are not accurate. One of the requirements for accurate hardness testing on sheet metal is two flat parallel surfaces. I have used about every type of hardness tester made.
1. Durometer for elastomers.
2. Portable drop weight tester.
3. Microhardness.
4. Rockwell hardness.
6. Brinnel Hardness.
7. Vickers hardness.

CatShooter:
After all of this discussion I get the impression that what you are doing is a very good method for shooters. I like the color of the cases. It looks like a factory job. We cannot build metallurgical labs in our basement to do quality control. The exact hardness and neck tension you get after annealing isn't important. What is important is to do it the same way each time so that you get the same neck tension on each case.

 

[jlow]

FWIW it should be obvious that the term red is a very general term. I too have heated my necks until they just turn red and no it is not lead soft. However I have heated them really hot and they are indeed like lead.

What I was trying to say with my comment that you actually quoted is the above which is heating it up until it turns red is not necessary the end of the world but the best method is to avoid that. Not sure why people get so worked up…. LOL!

 

[TC260]

I put this chart on the website several times. Here it is again. I cut the necks off of Lapua 6BR blue box cases and heat treated them in a lab furnace that controlled temperature to +/- 2 degrees F. Then I determined the hardness. Interpret it any way you wish. Looks like the important thing is to find a method you like that works and stick to it.

Did you post your process and procedures here sometime in the past for coming up with that data? I haven't been on the board for quite awhile. I searched around a little bit but couldn't find anything.

 

[WindSurgeon]

When I said "blue" I meant "color change". This happens in about 5 seconds.

Unless a person has over $400 (low end) to spend on a process controlled annealing machine that controls all the parameters of time, temp, and location of heat applied in concert, perfectly uniform annealing is not a reality for most. Just say'n. About all the masses can expect is longer case life and a bit more uniform seating force and neck tension (subjective).

It would be interesting to see what a person with a force indicator on a seating gauge (21st Century for example), or a testing machine with a force indicator pulling the bullets after seating, would say.

 

[CatShooter]

"... Unless a person has over $400 (low end) to spend on a process controlled annealing machine that controls all the parameters of time, temp, and location of heat applied in concert, perfectly uniform annealing is not a reality for most. Just say'n. About all the masses can expect is longer case life and a bit more uniform seating force and neck tension (subjective)."

I disagree... I use the Hornady kit (no Templaq), and anyone can do the same with sockets... it is very uniform and good accuracy can be achieved - I think you are being too theoretical (and anal) about it.


Done with a Hornady, and screwdriver - it works well.

 

[WindSurgeon]

I agree and that is my point. I don't think it can be proven that going to the extreme of an expensive piece of equipment has that much incremental benefit (I hope I am reading your reply correctly). I simply have always put the brass in a socket, turned it with a drill and put it in the flame. It works for me.

 

[dickn52]

I agree, and with my Giraud I can fill it, light it up, turn it on and walk away to do other things while it cranks out 200 or 500 rds at a time. But the end result will be very similar.

 

[tenring]

Any one have accurate knowledge as to how factory brass (i.e. Lapua or Norma) is annealed?