A Definitive study of Annealing

H

hounddawg

New member
I was over at the Savage Shooters website and came across a blog article written on the 7th of this month referencing a in depth study of annealing. AMP contracted METLAB to conduct a number of studies on the effects of case annealing and it's affect on neck tension and hardness. They then asked a couple of reloading experts Bill Gravit of Sinclair International and author Mic McPhereson to help them figure out what the results meant. The results can be found along with some interesting analysis by a couple of top experts here

https://www.ampannealing.com/articles/40/annealing-under-the-microscope/

It is of course a big sales pitch for the AMP annealer however it does scientifically demonstrate that annealing done properly will keep your cases in almost new condition. It also has lots of pretty pics, charts, and graphs along with links to the actual lab tests.

A couple of the more interesting points I saw not related to annealing were that ball neck expanders work harden the brass more than a standard neck sizer does and that it is better to leave a little bit of carbon inside the neck cases to act as a lubricant.

It's a worthwhile read for anyone whose goal is precision reloading
 
I figure it should stop any debate whatsoever on whether annealing is worthwhile. Now it is up to each individual reloader to decide how much time and money he/she wants to drop on it.

I am using a modded out Anealeez which I upgraded to a digital readout PWM (speed control) and doing some SD tests over the chrony. I am getting mixed results and will do a thread in a week or two if I can get the range time and can come to any worthwhile opinions on the effectiveness or not.

What I would have liked to have seen in those tests would have been some numbers ran on older brass that had been shot multiple times with no annealing. That seems to be the the big issue with my efforts so far although I am only on my third round and still experimenting with the time factor.
 
Hounddawg, for my part there's never been a question as to whether or not annealing was beneficial; for me the question has always been whether or not it was necessary.

Where I do most of my shooting, between 20% and 40% of the cases fired out of semiautomatic guns are "lost in the weeds". Only 38 Special and 223 from my bolt gun are fully recovered. Given my "loss rate", statistically speaking there are few cases in my reloading stream with 5 loadings on them and none with 7, so my brass is lost before it would need to be trimmed or annealed after it is initially processed.

People working with cases that work harden after only a few firings should consider adding the step to their processing, but it is a facts and circumstances determination.
 
"...stop any debate whatsoever..." HAHAHAHAHA. That's funny.
Annealing has one purpose and only one purpose. It extends case life. It does nothing for accuracy. Isn't necessary for any case except bottle necked cases or every time a case is loaded. And is very much not rocket science or magic.
It's trying to mechanize the process that causes most issues. That and heating the case too hot. As in red hot is too hot.
"..."lost in the weeds"..." Range tax and/or a sacrifice to the hunting/shooting deities. Works the same with arrows.
 
Annealing only good to extend case life?

Hey TO, speak for yourself. I have shot my bottle necks so much that some of the head stamps are getting pounded out, I went to annealing to extend the life, and improve my group sizes. I have been shooting the same group of cases from about 5 different calibers over and over this year, with every round going over my chrono. Interesting, my SD's haven't went to zero but are always below 15 (with only old abused brass), but, my targets have one sub MOA groups now with all 5 calibers. My 6MM cases were bought in the early 80's and were were getting to the point that 1/2 of them would have a split neck after firing. I have found one split neck in the last 3 loadings. The annealer upped my game, just like my chronograph.
 
As I said in my first post all this does is show through testing that annealing done properly will keep your cases in almost new condition. If that is important to you for whatever reason then anneal, it it is not then no worries.

I am annealing all my match grade cases after every firing now and I have noticed a lot less vertical spread on my groups at 300 and above. Not sure if that is entirely due to the annealing though since I am becoming more and more diligent at every aspect of my case prep
 
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Its some very interesting additional information.

I didn't find it negative in sales pitch terms. While it is aimed at the AMP and its programing it certainly has the open data that benefits everyone.

As there was no question as to it being effective in saving brass, I am not into that part.

It does indeed lead to some interesting insight into the carbon and what its affects are and raises some questions as well.


As for me and carbon, as noted by AMP it often emits as it cooks out and my results have been that the emission also removes any lubrication factor and I need to lube the bullets on the first round after anneal.

It does not seem like that would be exclusive to the Annie, they do make clear its just AMP related.

So I am scratching my head as to two meticulous researchers have found time is changed with clean vs non clean brass.
 
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@RC 20 my routine now is tumble in walnut with before depriming then anneal etc etc etc with no neck lube and I have been getting excellent results with my .260's as far as grouping and vertical dispersion. Looking into my cases I see a dark brown coating, nothing like the wet tumbled new brass look

Neck soot is going to cook off at xxx temp whether the heat was generated by a chemical torch or by magnetic waves. No biggie there.

If I understand your last question correctly when AMP sent the brass to METLAB they sent all of the batches uncleaned and new unfired brass. When they did the tensile test they noticed that the new unfired cases took more force than the dirty annealed cases even with the same neck tension and hardness.

According to the article AMP is planning on running a second round tests including more tensile tests using various neck lubes and cleaning methods.
 
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I have to say I found it curious that they did so many 0.003-.0035" interference fits, when most dies tend to give shooters about 0.001" to 0.002" interference. But I suspect they are on the right general track.

When RSI was still making their Load Force instrument, they had customers who claimed as little as one pound difference in seating force could be seen on target, and thus measured seating force became a sorting factor for them.

When Mr. O'Heir can show he has conducted experiments with properly controlled annealing and proven that such annealing has no effect on accuracy, then we will be happy to see his work. Until then, I can only assume his statement that it is "not rocket science" means he employs a simple and imprecisely controlled method. In that case it would be no surprise that he can't see any accuracy improvement as the resulting hardness levels would exhibit variation and their mean value is offset from the ideal value and differing from one annealing session to the next. So his statement that accuracy is unaffected by neck annealing may only be an indication that his particular method of neck annealing should be avoided.

Mr. O'Heir is, however, correct that the debate won't be ended by this study nor even by 100% scientific proof. The scuttlebutt to the contrary will persist. A friend of mine who is an attorney said his trial law professor told him that if you go to court 100% in the right and with all the physical evidence and proof on your side, your chances of winning a jury trial were about 60%. I think that provides some insight into the inability of some persons to understand what constitutes proof and what doesn't. It also tells you one reason attorneys like to settle out of court.
 
I am going to have to remember that 60%

I did send an email to AMP and this is what I got back.


"Further to my last email, I can confirm that if cases are annealed wet, straight out of the tumbler, it will affect the annealing result. The cases will be slightly under-annealed, and also the hardness will be more erratic. Cases should always be dried before annealing."

That then means they need a separate data set for brass cleaned with steel pins and solution.

As was noted previously, that is a lot of programing to keep up with.

As for the Carbon, that's my results. Its not an issue but its also a stray factor for the first round after annealing.
 
As for the Carbon, that's my results. Its not an issue but its also a stray factor for the first round after annealing.
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I agree that consistent neck tension and release is desirable and although I am getting acceptable SD's and groups there is always room for improvement. Neck lubing no matter what annealing process used might be a good idea, even if not annealing and using a wet/pin method and not annealing you should probably be using a neck lube. A Qtip with some mica/talc before seating will do the trick
 
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What bothers me is that they clearly said it was different, but then did not say they had program settings or offering settings that did account for that.

Yea, I know not to anneal a wet case. Not that I mind, but that was not the questions.

I will do some follow up of course.
 
hounddawg, Thanks! That's a marvelous study. I need to re-read and digest (old-brain syndrome here) but the micros and lab work are superb. Thanks.
 
@RC 20 - what bothers me is that with any other method than the AMP we are just guessing. Neither with the Annie nor my Anealeeze do we have any clue as to what we are actually doing to the brass hardness wise. Yes I can control the flame intensity and placement and the adjust the time but the reality is other than putting a bit of Tempilaq and waiting for it to melt is the best we can do. I would bet that even on the worst setting the AMP is doing a more precise anneal than we can ever do.

Now if I were using a AMP I could just pop the cases into the #11 shell holder and dial in program 91 for a .260 Rem with a .016 neck thickness and be reasonably comfortable that I was getting the proper anneal. As it is I think I am getting a good anneal and know it is a safe anneal and a reasonably consistent anneal but what is actually happening to the neck hardness I have not a clue.
 
I thought AMP was dialing in not only the chambering but the make of brass. May be remembering wrong, though.

Tempilaq should work if you know what value to use and for what length of time. That would require testing as well, though.
 
@Unclenick

over at their settings page they list over 40 brands and lot numbers of .223 all with different settings for each along with settings for each with .001, .002, and .003 neck turned versions. That is just the .223, they have settings for just about everything and if they don't have it send them a sample piece of brass and they will test it, recommend a setting and list it on the page giving you credit as a contributor


bah, I am not a wordsmith - https://www.ampannealing.com/settings/ check it out

For all of it's expense it sure seems that if the goal is a perfectly annealed case this thing is the best bet. Now all I have to do is convince myself that I need a perfectly annealed case :confused:
 
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T O'Heir wrote:
"'...lost in the weeds...' Range tax and/or a sacrifice to the hunting/shooting deities. Works the same with arrows."
Click to expand...

Early in my career, I worked as an agent for the Treasury Department, so I'll take "Range Tax" as its less likely to cause me to catch a lightning bolt than "shooting deities".
 
"Further to my last email, I can confirm that if cases are annealed wet, straight out of the tumbler, it will affect the annealing result.
Click to expand...

I would expect that response from a reloader. If I anneal a case that is wet I expect the wet to disappear long before the case sets hot enough to anneal. I said many years ago I decided to get into annealing, I decided there were rules and I decided there were factors. I talked to a reloader that claimed he used candles, it did not take me long to track that one down because the candle violated one of my rules.

Definitive? and then there is talking it to death.

F. Guffey
 
@RC 20 - what bothers me is that with any other method than the AMP we are just guessing. Neither with the Annie nor my Anealeeze do we have any clue as to what we are actually doing to the brass hardness wise. Yes I can control the flame intensity and placement and the adjust the time but the reality is other than putting a bit of Tempilaq and waiting for it to melt is the best we can do. I would bet that even on the worst setting the AMP is doing a more precise anneal than we can ever do.

Now if I were using a AMP I could just pop the cases into the #11 shell holder and dial in program 91 for a .260 Rem with a .016 neck thickness and be reasonably comfortable that I was getting the proper anneal. As it is I think I am getting a good anneal and know it is a safe anneal and a reasonably consistent anneal but what is actually happening to the neck hardness I have not a clue.
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Valid points.

As the grain exam and testing process they use are foreign to me, I don't know how to asses them (JH has not weighted in!).

If I am tracking it right, they cross compared grain structure r with hardness and then used hardness as the test to confirm most settings.

I do have some itchiness to my feelings on AMP when two piece of data are not matching what I have found (carbon burned in inductive is very sticky) and the detail that they acknowledge the fully clean brass need more anneal but they don't have a program selection for that.

More than agreed I would rather under anneal than over, so its a good factor but crosses with the perfect end result.

And if you read the Tempilaq Write-up, I did indeed have conflicting information and the mfg is sending me both 750 and 800 to test to resolve it.

AMP may well turn out the perfect brass.

For my ROI, I think the Annie does what I need (conservative anneal) at a price I can afford.
 
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