case annealing

Every now then then some gem of wisdom is passed along in these pages, kudos to BattleRifle.

Until now I've been annealing with the cartridge held in my fingers to ensure the case gets even heat all the way around, allowing my pain threshold to determine how much heat the case gets. For some reason the last few cases seem to get a little less heat than the first few, and the long cartridges more heat than the short ones. Go figure. I'm going to give Obtunded's technique a go. The heat crayon should keep the results uniform and I won't need to adhere to the "no pain no gain" philosophy anymore!
 
When using the temp crayon, I found that not all cases heat up at the same rate ie 5 secs for every cases. Some took longer, others shorter.

I didn't think work hardened cases would have different heat conductivities but me no engineer.

So I had my doubts on how well commercial annealers would work. They all function on time in flame to determine the annealing. If brass does change how it conducts heat, you will immediately get a range of ductility when done.

Likely it is how I held the case in the flame SO plan B is going to had some ideas from commercial units.

I am going to make a stand where the socket with brass can be located the same way. Then I will use 2 torches to put heat on the case neck from either side hopefully engulfing the necks evenly. I will not need to rotate the case.

With the temp crayon as my indicator, just heat until it goes puff then drop on a damp towel. I used to use a bucket of water but what a mess. I also much prefer the idea of air cooling but was afraid that heat might radiate to the base (?????).

Anyways, too cold to bother right now but will make for fun in the spring.

Jerry

PS Obtunded, thanks for the reference.
 
mysticplayer said:
With the temp crayon as my indicator, just heat until it goes puff then drop on a damp towel. I used to use a bucket of water but what a mess. I also much prefer the idea of air cooling but was afraid that heat might radiate to the base (?????).

Anyways, too cold to bother right now but will make for fun in the spring.

Jerry

PS Obtunded, thanks for the reference.
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I just do mine at the kitchen sink, and when my fingers get too hot, into the sink they go. Winters great, I can freeze my fingers shooting, then burn em annealing. :)
 
I have shot Winchester 308 cass 25+ times with only one neck trim.

I have only annealed cases when doing some radical case forming - say 25 - 375 H &H. Are you sure the cases need to be annealed?

The material above is an excellent primer on the subject. i hope somebody can post it as a sticky.
 
Not worth the effort for common brass, also has the potential to harm accuracy if not done consistently and correctly. I shoot em until they break and then they get recycled.

25 reloads with .308? I believe it, I have done it myself with 6.5 x 55...
 
fire

mooncoon said:
I anneal my cases every 4 or 5 shots. Sit them on an aluminum block in a bread pan of water with about 1/4" of water above the base of the shell. Heat to low red hot and tip into the water

cheers mooncoon
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I have read that if you heat them up until the are red that you are over doing it. FS
 
GANDERITE said:
I have shot Winchester 308 cass 25+ times with only one neck trim.
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I have not yet figured out the variable that causes splits. I have for a while now been running a batch of Winchester cases through my M14 for the sole purpose of monitoring the hardness, microstructure and time-to-failure. They have been loaded 8 times now and only one has developed a failure.

On the other hand, .308 R-P brass I had some years ago was splitting regularly in my A-Bolt after 3-4 firings.

As to annealing, when it is necessary, I have a new system. I use a Lee Precision Melter (forty bucks) to melt a bath of potassium nitrate salt. The melting point is 330C, and if I can find some sodium nitrate to blend with it I can depress the melting point further. I monitor the temperature with a thermocouple. The temperature can be controlled within a couple of degrees, and the heat transfer rates of a solid in a liquid bath are very, very high. I eventually plan to do a very thorough study of the effects of different annealing temperatures, and to do that I needed to control the heating rates very closely. I posted a lengthy description in this thread.
 
As for annealing not being a worth while step for normal brass, I'm not sure. As brass is fired and resized it work hardens the necks. As a result the grip on the bullet increases and pressure from round to round is less uniform. Perhaps it makes less sense for hunting rifle ammo where the life of the brass is only 5 reloads (like some of the Federal stuff I've used from time to time), but if you are loading expensive brass for your Rigby, Weatherby, RUM, etc., even one additional loading is a good thing. When you are attempting to wring the last possible bit of accuracy out of your loads in a target rifle, anything you can do to keep the variables consistent is also worthwhile. Because I'm cleaning my brass with an ultrasonic cleaner now, annealing adds little time to the process and will probably become a regular step in my case prep.
 
For the most part, heating the brass has few useable options.

However, is there a way to measure the ductility of the brass after annealing so you know where it's at?

Something that is simple and non destructive.

Most will use seating pressure as an indicator of progress but that is vague at best.

As we are trying to be consistent with neck tension, how do you measure this?

Jerry
 
annealing

All interesting reading, but as much as I enjoy the reloading process, I'm with the "shoot 'em till they split and dump 'em" crowd. Call me lazy, but I prefer to spend my time shooting rather than on complicated and onerous reloading chores.
Anything I can do to reduce the labour involved adds to my shooting pleasure.
Just added a digital powder dispenser to the armoury to that end. Prefer RCBS Competition Dies for the convenience of just dropping a bullet in the 'window' to get concentric bullet seating without damage to bullet bases.

The idea of water anywhere near molten metal scares the crap out of me as it does many others. Melting lead into ingots, I put some sheet lead into the pot that had been indoors drying for days. There was a bit of water somewhere in the mix and "POW!"; you know what happened.

Fortunately, I had just turned my back and taken a step away so I was spared except for some interesting lead patterns on the vest I was wearing.
The wall and roof of the shed are also quite decorated.

Until there is an affordable annealing gadget offered by the reloading companies, this is something I can live without doing.
 
mysticplayer said:
However, is there a way to measure the ductility of the brass after annealing so you know where it's at?

Something that is simple and non destructive.

Most will use seating pressure as an indicator of progress but that is vague at best.

As we are trying to be consistent with neck tension, how do you measure this?

Jerry
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Ductility is expressed as elongation to failure or reduction of area at failure, so it cannot be determined without testing to failure.

The only way I can think of to measure your neck tension would be to install a load cell on your press ram. This is hardly simple or low cost.

as much as I enjoy the reloading process, I'm with the "shoot 'em till they split and dump 'em" crowd.
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If everyone was consistently getting 10 or 15 loads out of a case, I would be in this camp, too. But we don't. I reload to save money, and the re-use of the cases is the biggest thing that makes that possible. So, I am trying to understand why some cases fail after only a couple of firings, and what I can do about it.
 
Andy said:
In a darkened room, with the propane torch on low, hold the case between thumb and index finger and rotate the neck area in the flame. Once the colour red begins to appear, dump it into cold water.
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2X except I do it outdoor during day time. I heat the case for 5-10 second before dumping into cold water.
 
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