How NOT to anneal your brass.....

I will have to try my hand at this in the near future. I thought the rule of thumb was not even a dull glow.....if I were to guess, one second after he hits the case he could dump it. Or less.
 
I've seen that one before - oh boy is he ever using way too much heat.

As well as only on one side of the case!

I have the Brass-o-matic annealing machine - it covers the entire neck and shoulder and only uses the outside edge of the 2 opposing flames for 6 seconds, on a 308 case.

Just turns a very dull orange and then it`s out of the flame - you`re done! They give some very good research for their machine, in their instructions. This explains the whole process they went through to find the correct dwell times in the flame, when they used Tempilaq.

Nice machine - I really enjoy annealing now. Kinda like the whole process of reloading - laid back take my time and let the machine do it all for me.

I just feed cases onto the turntable and they drop out on the end of the cycle.

Cheers, Carl
 
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The water does not temper the brass, the water only stops the annealing process at that particular point. The heat however has already OVER annealed the brass making it much softer than it ever should be.

Optimal Case Temperatures for Successful Annealing

Brass is an excellent conductor of heat. A flame applied at any point on a case for a short time will cause the rest of the case to heat very quickly. There are several temperatures at which brass is affected. Also, the time the brass remains at a given temperature will have an effect. Brass which has been "work hardened" (sometimes referred to as "cold worked") is unaffected by temperatures (Fahrenheit) up to 482 degrees (F) regardless of the time it is left at this temperature. At about 495 degrees (F) some changes in grain structure begins to occur, although the brass remains about as hard as before--it would take a laboratory analysis to see the changes that take place at this temperature.

The trick is to heat the neck just to the point where the grain structure becomes sufficiently large enough to give the case a springy property, leaving the body changed but little, and the head of the case virtually unchanged.

If cases are heated to about 600 degrees (F) for one hour, they will be thoroughly annealed--head and body included. That is, they will be ruined. (For a temperature comparison, pure lead melts at 621.3 degrees F).

The critical time and temperature at which the grain structure reforms into something suitable for case necks is 662 degrees (F) for some 15 minutes. A higher temperature, say from 750 to 800 degrees, will do the same job in a few seconds. If brass is allowed to reach temperatures higher than this (regardless of the time), it will be made irretrievably and irrevocably too soft.

Brass will begin to glow a faint orange at about 950 degrees (F). Even if the heating is stopped at a couple of hundred degrees below this temperature, the damage has been done--it will be too soft. From this discussion we can see that there are four considerations concerning time and temperature:

1. Due to conduction, the amount of heat necessary to sufficiently anneal the case neck is great enough to ruin the rest of the case.

2. If the case necks are exposed to heat for a sufficient period of time, a lower temperature can be used.

3. The longer the case necks are exposed to heat, the greater the possibility that too much heat will be conducted into the body and head, thereby ruining the cases.

4. The higher the temperature, the less time the case necks will be exposed to heat, and there will be insufficient time for heat to be conducted into the body and head.
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Brass is the opposite of iron. If one heats brass and slowly cools it will become brittle but rapid cooling softens the brass and makes it more flexible.

Cold working brass such as resizing and firing make brass brittle over time. This is where a flexible shoulder & neck lengthen the case's life.

The only danger with annealing is altering the metal's properties near the case head which is why water should be used.

This guy might want a little more water in the pan, a little less heat and do fewer at a time but he is not technically doing it wrong. Cheers!
 
Cases are heated then air cooled in ammo factories, either by flame or induction. Generally they just drop from the annealing line into a container, where they cool.
 
This is a great article on annealing.

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

BTW, I have some 650° F Tempilstik that will be posted in the EE in about a week (cheap too). They work OK, but brass is a bit smooth for them to leave a lot of material on it.

You only need to mark a couple cases so you "get the feel" of how much (or little) heat you need.

I am going to be experimenting a bit to see if making a paste from the sticks works better and still give accurate temp readings.
 
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rightroad said:
Brass is the opposite of iron. If one heats brass and slowly cools it will become brittle but rapid cooling softens the brass and makes it more flexible.
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Sorry, but no. Cooling of brass in water only stops the annealing process, does nothing to the physical quality of the brass.

See CyaN1de's post and the link I posted above.
 
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I think the yellow white colour of the neck might be partially an artifact of the camera. If the brass was really that hot, I would expect it to melt or at least slump. At least that is what happens when I get it nearly that hot :>)

cheers mooncoon
 
mooncoon said:
I think the yellow white colour of the neck might be partially an artifact of the camera. If the brass was really that hot, I would expect it to melt or at least slump. At least that is what happens when I get it nearly that hot :>)

cheers mooncoon
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I don't think so, it might be a bit as a result of the camera, but judging by the length of time he held the torch on each case, the brass will be permanently softened.
 
"...It is a common way to anneal brass..." Yep, but Bubba is heating to red hot. That's too hot. Heat with a regular propane torch until the brass changes colour then tip 'em over.
 
I have annealed that way, though even in my dumbest days I didn't use anywhere near that much heat. It isn't smart and it will be hard on the brass, but it isn't really dangerous, and the cases will probably last longer than if he didn't anneal at all.

There is no such thing as permanently softening brass. The grain size will be HUGE, giving him very soft cases for a while, but a few passes through the die and rifle and it will eventually work harden again.

tps50701 said:
I have the Brass-o-matic annealing machine - it covers the entire neck and shoulder and only uses the outside edge of the 2 opposing flames for 6 seconds, on a 308 case.

Just turns a very dull orange and then it`s out of the flame - you`re done! They give some very good research for their machine, in their instructions.
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Carl, I don't suppose you would be willing to get me a copy of those instructions and research?
 
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