Annealing Last

[kvd]

I’ve decided to modify my reloading procedure in order to place annealing at the end of the process, after ultrasonic cleaning, and prior to reconstructing a loaded round with primer, powder, and bullet. My logic for doing this is as follows: According to information available on the AMP website, the actual firing of a cartridge does not affect the hardness of the brass significantly. That would seem to indicate that if the cases were annealed prior to firing, after firing they would be in essentially the same condition and would not be damaged by the reloading process without first annealing. Granted, we all do things a little differently but in general, returning an empty case to the point that it is ready for reloading usually involves full length sizing, case trimming, neck sizing, neck expansion ...etc, with varying degrees of cleaning in between. Again according to AMP’s website, these operations will add approximately 30 HV in work hardening to the neck/shoulder area of the brass case. In order to achieve the most uniform neck grip, this work hardening should be removed by annealing prior to seating the bullet.

Early results of this change look promising. Time will tell if annealing at the end of the process is better than after initial cleaning – as I was doing before. Others may have already come to this conclusion and it seems to make sense to me.



Ken

 

[ngb1787]

I do the same, results are great, consistant 5.0 SD, time after time.

 

[shoot4fun]

Are you saying you do the FL sizing BEFORE you anneal? Seems like that heat would distort the sizing you just did. After all, annealing is done to soften brass and, in a sense, relieve stress at the juncture of neck/shoulder. How do you keep the head space correct and consistent after anneal?

 

[Zero333]

I tried it as a last step before prime/powder/bullet, but didn't like how easy bullet seating felt. Gave me the impression that Bullet neck tension was much less than usual. Since I magazine feed much of what I reload I anneal before sizing.

 

[Willie]

Are you saying you do the FL sizing BEFORE you anneal? Seems like that heat would distort the sizing you just did. After all, annealing is done to soften brass and, in a sense, relieve stress at the juncture of neck/shoulder. How do you keep the head space correct and consistent after anneal?

I considered this approach, but in the end, had the same concerns. I think I'll stay with annealing prior to resizing. Most of my rifles will shoot 5 shot groups with ES hovering around 10 fps, with this method. I am open to reconsidering, if someone has the time and barrel life to test this. On a batch (brain fart acknowledged) I resized without annealing, found a full .001" difference in base to datum. Whatever the cause, it showed on paper.

 

[noload]

I've done the anneal after sizing and it works out fine. I can't see a definitive difference.

 

[moajoe]

I just switched to annealing as the last step in my case prep routine. The bullets do seat with less resistance in my case and they seem to be consistent through out the batch I am working on. I am looking for those rounds to being close together as far as neck tension goes.

 

[Gina1]

Are you saying you do the FL sizing BEFORE you anneal? Seems like that heat would distort the sizing you just did. After all, annealing is done to soften brass and, in a sense, relieve stress at the juncture of neck/shoulder. How do you keep the head space correct and consistent after anneal?

+1

Anneal first.

 

[kvd]

Are you saying you do the FL sizing BEFORE you anneal? Seems like that heat would distort the sizing you just did. After all, annealing is done to soften brass and, in a sense, relieve stress at the juncture of neck/shoulder. How do you keep the head space correct and consistent after anneal?

Yes - annealing does not heat the case hot enough to distort it - if it is being done correctly that is.

I tried it as a last step before prime/powder/bullet, but didn't like how easy bullet seating felt. Gave me the impression that Bullet neck tension was much less than usual. Since I magazine feed much of what I reload I anneal before sizing.

You are right in that if you established a good neck grip annealing early you would need to continue doing it early in the reloading process - or revisit the neck grip after annealing. Bullet seating does seem more consistent when annealing is the last step.

Ken

 

[Willie]

Ken,
What is your neck treatment after annealing? Brushing, lube, etc?
I reread your post about ultrasonic cleaning and wondered exactly what your method is. Thanks

 

[kvd]

Ken,
What is your neck treatment after annealing? Brushing, lube, etc?
I reread your post about ultrasonic cleaning and wondered exactly what your method is. Thanks

Basically, I do this:

• After returning from the range, I put all the fired cases straight into the vibratory polisher with corn cob media for six to nine hours.
• After removal from the polishing media, spray inside and outside of the cases with lanolin/isopropyl alcohol mixture for case lubrication
• Full length size to move the shoulder back 0.001 to 0.002 inch max and deprime (no neck bushing or expander button installed in die)
• Neck size
• Expand neck
• Ultrasonic clean to remove residual case lub and clean up the inside of the case and primer pocket
• Anneal
• Prime
• Charge case
• Seat bullet

A lot of measuring and checking is happening between and during the above steps which may require an additional step or two such as case length/case base measurement after FL sizing.
One other point should be stated. We want the base and body of the case as hard as possible. Full length sizing without a neck bushing or expander button installed will put very little stress into the neck/shoulder area of the case if full length sizing is accomplished before annealing - especially if the annealing done previously has not been significantly changed by firing the round as the AMP folks have determined.

Ken



​

 

[Mulligan]

Tag

 

[shoot4fun]

Yes - annealing does not heat the case hot enough to distort it - if it is being done correctly that is

Ken

I've thought about this statement and just don't understand what you idea of "distortion" is.
Annealing is designed to bring brass back to a "softened" condition and prevent not only cracking/splitting but to keep the cartridge case from developing a memory. There is enough heat applied (if done correctly) to accomplish allowing an already FL sized case to change dimensions so you will, in my mind, lose the shoulder set back you are achieving with FL size die.
I am not a metallurgist and not an indisputable expert on the art of annealing or the properties of brass but it just seems like anneal as the last step before loading is not the best way to do it.

 

[T-shooter]

I considered this approach, but in the end, had the same concerns. I think I'll stay with annealing prior to resizing. Most of my rifles will shoot 5 shot groups with ES hovering around 10 fps, with this method. I am open to reconsidering, if someone has the time and barrel life to test this. On a batch (brain fart acknowledged) I resized without annealing, found a full .001" difference in base to datum. Whatever the cause, it showed on paper.

I agree. Annealing first allows the brass (including the shoulder area) to conform more easily to the die. I doubt if there is enough work hardening to matter by resizing. Besides, if you do a batch of cases, they should all be the same.

 

[kvd]

I've thought about this statement and just don't understand what you idea of "distortion" is.
Annealing is designed to bring brass back to a "softened" condition and prevent not only cracking/splitting but to keep the cartridge case from developing a memory. There is enough heat applied (if done correctly) to accomplish allowing an already FL sized case to change dimensions so you will, in my mind, lose the shoulder set back you are achieving with FL size die.
I am not a metallurgist and not an indisputable expert on the art of annealing or the properties of brass but it just seems like anneal as the last step before loading is not the best way to do it.

Hi shoot4fun,

When I say distortion, I'm referring to any changes in dimension. Annealing of cartridge brass occurs rapidly at approximately 800°F ± 25°F. This temperature is not hot enough to change any dimension of the neck/shoulder area of the cartridge case. What annealing will affect is the spring-back inherent in the neck of work hardened brass versus annealed brass. By annealing as a last step, I'm willing to accept a small amount of potential spring-back in exchange for the most uniform hardness in the neck area I can get. I might mention that none of my reloading sizings are extreme. By that I mean that most of the time, I barely can tell I'm doing anything at all to the cartridge.

Ken

 

[Sheldon N]

Fundamentally doesn't annealing last assume that your gun will shoot better with less neck tension? I would think that's something you'd need to test.

My guess is that the difference in neck tension between brass that is annealed-sized-seated compared to brass that is sized-annealed-seated may have a bigger impact on how your gun shoots than any differences in consistency between the two processes.

 

[R.Morehouse]

I do it before sizing. I guess that as long as you do it in the same order and your results on paper lead you to believe it is working for you.........There you have it..........I have never heard of anyone doing it post sizing before now. Thanks for putting it out there........

 

[kvd]

However one is set up to do annealing - the target will ultimately be the final arbiter of what is working or not working for your particular combination of variables. Any given change may yield even more accuracy than what we were doing before but as we know - every change must be evaluated for its effect at the target.

Ken

 

[shoot4fun]

Hi shoot4fun,

When I say distortion, I'm referring to any changes in dimension. Annealing of cartridge brass occurs rapidly at approximately 800°F ± 25°F. This temperature is not hot enough to change any dimension of the neck/shoulder area of the cartridge case. What annealing will affect is the spring-back inherent in the neck of work hardened brass versus annealed brass. By annealing as a last step, I'm willing to accept a small amount of potential spring-back in exchange for the most uniform hardness in the neck area I can get. I might mention that none of my reloading sizings are extreme. By that I mean that most of the time, I barely can tell I'm doing anything at all to the cartridge.

Ken

Sorry but I just don't see your logic. We will just shake hands and go our own way.
It would seem that proper annealing followed by proper sizing would provide the same consistency in hardness of the neck and leave you with piece of mind that the shoulders were all consistently set.

 

[Sheldon N]

Any given change may yield even more accuracy than what we were doing before but as we know - every change must be evaluated for its effect at the target.

Absolutely. The caveat in the context of this discussion would be that determining whether annealing first or annealing after is a universally better process can't be determined by how one gun responded to the change. Results on target might improve with the changed process, simply because reduced neck tension worked better for that gun. The reduced neck tension could also have been accomplished through sizing dimension changes. Similarly, if the gun shot worse because of reduced neck tension that could also be offset by a change in sizing dimension prior to annealing so that the total neck tension was back in the ideal range for that load.

I would think the best way to test this is to have someone like AMP do a large sample of brass through both processes, then measure brass hardness with each process just before seating to see if there is any appreciable difference in the consistency of brass hardness from case to case.