Case Annealing Question

[hrfunk]

I have been reloading for many years, but have recently started to load my first ever magnum rifle cartridge (300 WM). As I understand it, case annealing for this cartridge is a pretty common method for maximizing case life as well as maintaining peak accuracy. Having never annealed any cases, I've been trying to research the process, but the more I read, the more confusing the topic becomes. There seems to be a great deal of contradictory information out there. So with that introduction, here are my questions: 1) I am neck sizing my brass for the 300 WM, does the brass even need to be annealed? 2) If the answer to #1 is "yes", how many firings should the case undergo before it is annealed? 3) Is there a good information resource on the annealing process to assist a beginner?

Thanks,
HRF

 

[Graham]

A wise man once said that the answer to almost any non-trivial question is: It depends.

1) Why neck size? 'Need' to anneal? According to whom/what?
2) How can you tell?
3) No. It's not a beginner process. But there are Threads here on it if you want to play.

Here's what I do: Buy good brass. Then, when the reason to anneal presents itself... Throw out the existing brass and prep some new brass.

 

[Sniper Uncle]

http://www.6mmbr.com/annealing.html

Not sure how to make this show as a link, but this url should answer a lot of questions for you. It shows some pretty high-tech and "expensive" equipment, but you can get by with a drill, a driver bit for said drill with a square on it, capable of taking a deep-well socket of size to "fit" you case comfortably but not too loosely (I recommend an impact socket for more heat retention), a bucket with some water (some would argue this, but it won't hurt, as long as you dry them well---suggest the oven on a shallow pan set at about 180-200 degrees), and a propane torch. One poster to SH suggested, and I agree, easier to do in a semi-dark room, as you can see the brass start to change color better. I run the drill at a slow speed, with the flame-tip on the neck/shoulder juncture, and heat for about 8 seconds. I got some tempilstic, tempelaq works well.
As the article noted above says, I got 750 degree, and applied it on the outside of the neck/shoulder. Some of the reloading component sellers sell 475 degree tempilaq and this I believe you would put on the inside of the case neck. When heated enough, the tempilstic/tempelaq melts, telling you you are done. I found this to be consistenly at 7-8 seconds. Most of the other guys who contributed said very similar times regardless of the type of temp checker used.
Good Luck.

 

[lanwickum]

I have a $500 annealer. Is it worth it. I would give the advise Graham gave above to any beginner. I do enjoy the reloading process enough to not regret it. You will waste some brass getting everything setup and working correct. Don't try it for 20 or 50 pieces. Just buy new at that point.

Now, if brass really NEEDs annealed, it is probably worn out enough to replace it. I would consider NEED as when the necks will start cracking. This is different with each rifle as to how many firings you will get. I had one 7WSM I had 10-12 firings and never did a thing to the brass after the first full prep other than a resize and clean. The barrel wore out before the brass. Others that only 3-4 firings and the necks were splitting. I have one old military rifle that splits some necks on the first firing with the old ammo I have for it.
I use my annealer mostly when I am running a 1000 or more brass through the prepping process. I have an nice trimmer I also use during this. It is usually Lake City once fired brass I got cheap. I am trying to make it shoot as good as once fired win brass. I mostly do this with .223 brass for use in my AR and I have done a bunch for my 308 that turned out good enough I even used it in a few field matches. It is cleaned, trimmed, and annealed, nothing more.
Good luck and be safe.

 

[Graham]

Exactly: Annealing is a solution in search of a problem.

 

[ShtrRdy]

My limited experience with 300 WinMag brass is more of a concern of head separation. Neck/shoulder annealing won't help that problem at all.

 

[ZiaHunter]

I load 300 WM and to answer your question annealing will in most cases extend your case life and how many more firings it will provide is dependent on a number of factors. Annealing will provide more consistent sizing and neck tension since the hardness of the brass will be uniform. The single most important factor in extending brass life in belted magnums is proper sizing and oversizing the brass is probably the single most cause of short case life. Once fired, the brass should only be resized a minimal amount when FL or body sized with the shoulder set back .001 to .0015. By doing so the case will headspace off the shoulder and not the belt. I neck size up and until they chamber tight and then body size. I shoot only Norma brass in my 300 WM and typically anneal after three firings. I used to anneal by hand but eventually went to a machine in order to get more consistent results. Lots of threads and video's on annealing and would research them.

 

[msiebert]

"I would consider NEED as when the necks will start cracking."

When the necks start cracking you are too late...further if someone thinks "annealing is a solution looking for a problem"....well, I guess you haven't had the problem. It seems as though many shooter/reloaders dont get why brass would need annealing to begin with. Here is my version, right or wrong it's worked pretty good for me. First off, brass hardens, and it does it two ways as far as reloaders are concerned. One is with age. Very simply, brass that has sat for a long time will be hard. Second is what is called work hardening and it happens a little each time the case is fired {expanded} and then resized. Depending on the alloy age hardening alone can split brass. Likewise the number of times it has been fired and loaded can vary with different cases and happens more if sizing up or down to different calibers. Necks splitting is not the biggest reason most shooters anneal. While that is certainly a problem most cases need or could benefit from annealing long before they ever get that hard. It has more to do with neck tension on the bullet and can be seen on a chronograph and on a target. When good quality match type ammo is loaded to the best of your ability and fired out of a first rate really nice rifle with a broke in and clean custom barrel but the velocity from shot to shot varies by more than 5 or 10 FPS it is usually time to anneal the case necks. I discovered this back in 1994 by accident. Me and a buddy could never get our rifles {308's at the time} to shoot with velocities closer than 35-50 FPS on his chrono. We always wondered why and thought it was many different things, each one we attacked but never saw things change much. I had a metric shit ton of Lake City 57 brass. I noticed that everytime I sized the stuff it would make a "chirp" noise when it was pulling back out of the die over the neck expander ball. Eventually it didn't matter if I lubed the inside or not, it made the noise and got harder to size and retract out of the die each time. I realized it was work hardened and had at a few cases with a propane torch. I never at that point made the connection with velocity spread...next tiime we went shooting I shot one of my best groups ever with the three "foulers" while my buddy looked at the chrono in amazement. "What in the hell did you do to those loads!!!!!" And I been doing it ever since...."solution looking for a problem"??? Maybe for you. Ask yourself this: would you go and try to compete with every other cartridge having the bullet crimped in place as hard as you can squeeze it and shoot that way or would you feel alot better going into competition with all the necks having as close to the exact same tension on your bullets in every round???? So much for a solution looking for a problem.

 

[Deadshot2]

It's not necessarily a case of what one "needs" to do as much as what one "wants" to do.

I anneal all my .308 brass because I want to. I have found that I can load commercial brass like Winchester or Federal for as many as 20 loadings before I see any failures other than a loose primer pocket or two. Lapua brass goes twice that which is great because it costs almost twice as much

Annealing only benefits the life of a case in the neck area so if there are other common areas of failure it won't help. That said, I find that annealing leads to more uniform neck sizing when bushing sizing only. Annealed brass has the same spring-back as opposed to work hardened brass that's been sized/fired several times.

In the end, is it necessary? That's up to the person doing it. I don't bother with my .223 brass as I'm pretty much knee deep in it and still get 4-5 loadings out of what I have. I'll never live long enough to use it all up, tossing those pieces that split the necks.

 

[hrfunk]

Thanks for the info guys. This is exactly what I was trying to find out. I think I'm on the right track with the 300 WM. I'm neck sizing to allow the cases to head space on the shoulder, and hopefully reduce the likelihood of head separation. This seems to be working, I tried the paper clip test a few days ago and I can't detect any sort of abnormality inside the cases after 3 firings. I am, however, seeing higher ES and SD numbers than I would like. Usually a pretty good string is skewed by a few high or low anomalous readings. I'm suspecting that varying neck tension is the culprit, and I believe annealing the neck/shoulders might be the solution. Thanks again,

HRF

 

[J-ROD]

i found after 3-4 cycles on my brass, my groups/ES would suffer significantly. annealing fixed that as well as made resizing and seating much more consistent. i anneal every time now just to keep things the same. any case life i get is a bonus. i'm not shooting to see how many times i can reuse my brass, i'm shooting to see how consistently accurate i can be.

 

[sinister]

Shooting a .300 Win Mag with the belt, this may be applicable for you (a collet die to keep case body dimensions within spec -- keeping in mind the cartridge headspaces on the belt and not the shoulder):

Belted Magnum Collet Sizing Die -- http://www.larrywillis.com/

 

[armorpl8chikn]

The article Sniper Uncle has referenced is as good as you will get in info on annealing. I know Jim Harris through IHMSA. He has probably won more trophies for pistol silhouette than you could pile in the back of your full size pickup. Pistol silhouette is by nature a long range endeavor requiring extreme accuracy out to 200m...with a pistol. It requires at times hitting a half size chicken's kill zone at 200m as many as ten times in a row...sometimes more in the NRA long run record program. That kill spot is about the size of a standard baseball. No bipods, no bench. Not everyone has the skills Jim has, so whether it will benefit you can only be answered by you. To say it is of no use would be tantamount to telling Jim he doesn't know what he is talking about. It works for him.
I have seen several references on 6br site, to record setting BR shooters who swear by annealing. It does have value but maybe not for everyone. I anneal every so often. If your loads are hot then your primer pockets may give up first. I do know that annealing properly will give very consistent bullet pull even without bushing dies. Some folks anneal every firing. It is easy to master with minimal tools but the machines are very nice. I have had very good results with simple tools so I don't advocate the expensive machines unless you have a large disposable income. You can buy a lot of brass for the price of a machine, so maybe what Graham said would suit you best. If you go with the torch method you can expect to lose a few cases to mistakes. I can send you some scrap 300WM cases for practice if you drop me a line.

 

[Sniper Uncle]

I agree with you chikn, you will want to plan on losing some brass while you figure out your method. I used some berdan primed 1x-shot military brass to develop my method. That way, any that I lost were not really that much of a loss. Now that I've got a method that seems to work well, I'll do some other brass that I have. If I lose a few of them, the number that I successfully extend the life span of will more than outweigh any losses. It is nice to have some brass that you don't care too much about to learn on.

 

[bower4311]

http://www.6mmbr.com/annealing.html
As the article noted above says, I got 750 degree, and applied it on the outside of the neck/shoulder. Some of the reloading component sellers sell 475 degree tempilaq and this I believe you would put on the inside of the case neck. When heated enough, the tempilstic/tempelaq melts, telling you you are done. I found this to be consistenly at 7-8 seconds. Most of the other guys who contributed said very similar times regardless of the type of temp checker used.
Good Luck.

I've always seen apply 650 or 750 to the inside of the case neck, when it heats through, it melts. Then Clean the inside of the neck with a brush. Or, you put 475 degree tempilaq BELOW the shoulder so that when the top gets heated and starts to spread down to below the shoulder, at 475 when it melts you can assume that the top has reached a higher temperature sooner, being around 650-750.

I've said before, I would LOVE to see someone try both if they already have them, to determine if they're both accurate. If so, I would prefer to use 475 below the shoulder to eliminate any cleaning of the inside of the neck.

To OP:
If you do some searches on tempilaq, you will find most people say it's a very easy process to do, and once you use the tempilaq enough and get consistent results you won't need to use it anymore. Full length then anneal, if you're not shooting hundreds per week, it won't eat up too much of your time.

 

[afrancke]

The proper use of the Tempilaq is high (threshold) temp inside a case neck and low temp halfway down the case body. There is harm to going too far past the upper temp so I've never seen it suggested (but I am suggesting here) that perhaps a third stripe of limit (max) temp inside the neck alongside the threshold temp stripe would do the trick.

I have seen it asserted that time under temperature matters and not just hitting the upper limit (annealing threshold) at the neck and avoiding the lower limit mid-body, which makes sense. Presumably to get things really dialed in requires some metallurgical analysis to observe the material change properties under a microscope or some such. Far more than anybody will care to do for casual hobby loading! These same spoilsports also disapprove of heat treating the fire control pin holes on AK receivers with MAP or propane torches by "color."

 

[Sniper Uncle]

The proper use of the Tempilaq is high (threshold) temp inside a case neck and low temp halfway down the case body. There is harm to going too far past the upper temp so I've never seen it suggested (but I am suggesting here) that perhaps a third stripe of limit (max) temp inside the neck alongside the threshold temp stripe would do the trick.

I have seen it asserted that time under temperature matters and not just hitting the upper limit (annealing threshold) at the neck and avoiding the lower limit mid-body, which makes sense. Presumably to get things really dialed in requires some metallurgical analysis to observe the material change properties under a microscope or some such. Far more than anybody will care to do for casual hobby loading! These same spoilsports also disapprove of heat treating the fire control pin holes on AK receivers with MAP or propane torches by "color."

Yes, sir, you are correct, it is time at temperature that is critical. At 650, you need about 10-15 minutes, I don't know the exact time. At 750-800 a matter of seconds is sufficient. Problem is, if you go over 800, the time gets drastically reduced, and the danger of over-annealing is very high. That is the reasoning in trying to go for 750 on the temp indicator---you get it up to temp, and then cool it relatively quickly, getting the required time but not too much. It isn't quite as exact as I'd like, but it's the best I've got.

OP, I appreciate your starting this thread, as I have learned a fair amount from the post to it. Thanks everyone for contributing.

 

[X-fan]

I used to throw out my brass as soon as the necks began to crack.
For the beginner I think this is the smart way to go.

Many folks successfully anneal with the old torch and twirl method, but as in all forms of projects that require skill as well as some good judgement there are Darwinistic folk that should avoid this project.
Anneal the case head=blow up your rifle.

If your goal is only to stop your cases from splitting the cookie sheet with water or twirl method is fine. Back in the dark ages I annealed in the dark and stopped the moment I saw color appear....not very sophisticated, but plenty good enough to stop my cases from splitting and I never had an issue with poor extraction either.

If your goal is precision then my preference is something like the Bench Source annealing machine.
Not cheap, but if you are sporting a $6,000.00 rifle and a $3,000.00 scope it fits in well with that sort of quality level and those precision accuracy goals.

Good luck!