Annealing case necks

[FAsmus]

Gentlemen;

My 7x57 case necks needed to be drawn back soft - I was loosing about 1.5% every time I reloaded them due to cracks.

I lit-off my plumber's blow torch and, with a pail of water right close I began.

My technique is to hold each (de-primed) case by the head in my bare fingers and put the neck right into the hottest part of the flame.

Holding the head bare-handed makes it a certainty that I will not anneal that part of the case. The heat of the torch quickly gets the neck red-hot and I dump it into the water to quench just as the head is getting warm in my fingers.

When done each case shows how far down the annealing went ~ just past the shoulder. And the procedure goes quite fast.

Then all that remains is to dry the cases - usually in the sun - and carry on for another reload.

Good morning,
Forrest

[max range]

I do the same thing but I stand the cases up in a cake pan of water. I put templac on a few of the cases so I can judge the duration of the flame. When the proper temp/time is achieved I just flick knock the case over into the water. Bob Chow showed me that method and its worked fine for me.

[grampa243]

red-hot is too hot. better to just see the color start to change at the shoulder.

i use a socket in a handdrill at slow speed.

[Von Gruff]

red-hot is too hot. better to just see the color start to change at the shoulder.

i use a socket in a handdrill at slow speed.

Yes, grampa has it right, if you look carefully you can see the blue come down the shoulder and over onto the case wall in good light. That is the time to stop the heat and it dose not require being dropped into water either.
I have three different sized sockets (four now with my 6.5 GM needing one of its own) and drop them out of the socket into a steel bowl to cool in thier own time.No drying of unessarily wet cases to do and some of my 7x57 cases have been fired over 40 times. Anneal every 5th sizing as a matter of course now.

[FAsmus]

Gentlemen;

I forgot to mention that I use my method in dim light - this makes it easy to judge how hot the necks are getting - Just dull red, nothing outa sight like cherry red or orange.

I never heard of air-cooling to anneal nonferrous material. ~ I did check and air-cooling is a possible alternative to quenching, but wouldn't that risk over-heating the heads of the cases and softening them up? ~ Very risky stuff here. That is why the "safe" method of setting cases in shallow water and tipping them over when the necks get hot to quench has been the published/approved method for years and years.

Good evening,
Forrest

[jmorris]

You don't need any sort of glow of any kind to properly anneal cases. In fact, if you are using propane you don't even want the flame to change from blue to orange and it does that before the case "glows".

This is too much.



This is what you want. Flame remains blue throughout the process, even color and cool to the touch.

[Love Life]

Jmorris-You're my awesome reloading equipment hero.

[grampa243]

Gentlemen;

I forgot to mention that I use my method in dim light - this makes it easy to judge how hot the necks are getting - Just dull red, nothing outa sight like cherry red or orange.

I never heard of air-cooling to anneal nonferrous material. ~ I did check and air-cooling is a possible alternative to quenching, but wouldn't that risk over-heating the heads of the cases and softening them up? ~ Very risky stuff here. That is why the "safe" method of setting cases in shallow water and tipping them over when the necks get hot to quench has been the published/approved method for years and years.

Good evening,
Forrest

as soon as the heat is removed the brass begins to cool. also if using a socket it will work as a heatsink keeping the base of the shell cool. my sockets have never even got warm to the touch. as we know many have held the brass by the base when annealing. the brass does not soften till 450 deg. if you can hold 450 deg. and not get burnt i think you have other things to worry about then brass.

[doctorggg]

I use two butane torches pointed toward each other. I was using my Hornady annealing shell holder and holding the shoulder at the tip of both torches. Rotating with an electric drill. Usually I can count to 1005 or 1006 and drop most cases in the water.
I was annealing some once fired mixed headstamp 7.62x39mm brass cases tonight. I could get up to 1012-1013 and the necks never began to glow. Is there something different about this case. Win, PMC, Fiochi etc? I dared not exceed 13 seconds. The cases do not show much annealing? Suggestions?

[Recluse]

red-hot is too hot. better to just see the color start to change at the shoulder.

Gentlemen;

I forgot to mention that I use my method in dim light - this makes it easy to judge how hot the necks are getting - Just dull red, nothing outa sight like cherry red or orange.
Forrest

I pull the shades in my reloading shop then turn out the lights. This gives me just enough ambient light to safely see what I'm doing.

I hold the cases while wearing a glove, but the instant I see the hint of a "glow" on the brass, into the water it goes. You don't have to heat brass to the point of glowing in order to do a successful annealing job.

[220swiftfn]

Gentlemen;

I forgot to mention that I use my method in dim light - this makes it easy to judge how hot the necks are getting - Just dull red, nothing outa sight like cherry red or orange.

I never heard of air-cooling to anneal nonferrous material. ~ I did check and air-cooling is a possible alternative to quenching, but wouldn't that risk over-heating the heads of the cases and softening them up? ~ Very risky stuff here. That is why the "safe" method of setting cases in shallow water and tipping them over when the necks get hot to quench has been the published/approved method for years and years.

Good evening,
Forrest

The way you're doing it, you run the risk of turning the necks into copper by burning out the zinc from the brass...... As others have stated, do it in good light and watch the color ring, taking the case out of the flame when that ring hits the shoulder/body junction.


Dan

[Coug91]

PM sent

[Jack Stanley]

I've done annealing both ways and holding the case in the fingers has worked well for small batches . I did a batch of .223 cases on the machine the other day and used one torch instead of two . Time was set a 3.1 second in the flame and I didn't see any color change in the case untill it came out of the flame . Then , about two seconds after it was out of the flame I could see the shoulder turn a light blue . Now that was most enlightening to me .

Jack

[doctorggg]

Sorry Op if I am butting in. If the annealing took place you should see a color change in the brass neck after it cools, correct???

[FAsmus]

Dan;

You say: The way you're doing it, you run the risk of turning the necks into copper by burning out the zinc from the brass...... As others have stated, do it in good light and watch the color ring, taking the case out of the flame when that ring hits the shoulder/body junction.

Me: I've been around foundrys and metal-working industry in my life and I've seen zinc burn both from galvanized pipe being cut with a torch and when a melt receives zinc to change the percentage as required for a given alloy of brass.

Both examples are far, far beyond the temperatures involved by use of a mere plumber's gasoline blow torch heating a case neck for 10 - 15 seconds!

Where did this urban myth originate?

Not only that, when rubbed with steel wool to remove any oxidation my case necks are bright, shiny golden brass.

Good evening,
Forrest

[220swiftfn]

Dan;

You say: The way you're doing it, you run the risk of turning the necks into copper by burning out the zinc from the brass...... As others have stated, do it in good light and watch the color ring, taking the case out of the flame when that ring hits the shoulder/body junction.

Me: I've been around foundrys and metal-working industry in my life and I've seen zinc burn both from galvanized pipe being cut with a torch and when a melt receives zinc to change the percentage as required for a given alloy of brass.

Both examples are far, far beyond the temperatures involved by use of a mere plumber's gasoline blow torch heating a case neck for 10 - 15 seconds!

Where did this urban myth originate?

Not only that, when rubbed with steel wool to remove any oxidation my case necks are bright, shiny golden brass.

Good evening,
Forrest

Ok, perhaps a bit too "dumbed down" in my response, but still valid. If you were to take two pieces of brass, one annealed the way I describe, and the other heated to glowing, and squeezed the neck (by the same amount) in a vise, the one heated to glowing would NOT spring back like the correctly annealed one would. Weaker neck, less bullet pull. The difference is more than skin deep, it's structural. BTW, that yellow/orange flame is the zinc burning, you're changing the composition at that point........


Dan

[cbrick]

Here's an article that explains annealing very well. My own experience with annealing is that it is a bit of an art form. Get it wrong and you have either ruined your brass or accomplished nothing. Practicing on old scrap brass is recommended until you have the experience to get it right.

When, why, how and if to anneal
By Ken Light

Rick

[FAsmus]

Dan;

I see where you're coming from.

In my view consistency is the name of the game. Here, my method virtually guarantees that each case is annealed the exact same amount. This happens because my tender little fingers always reach that certain level of discomfort each time a case is in the flame ~ and then they're quenched.

How in the world do you tell the difference between "zinc burning" and residual bullet lube or other contaminants burning off the case?

I have seen zinc actually catch fire. It always burns with a bright blueish-white flame - nothing like yellow/orange.

Good morning,
Forrest

[FAsmus]

Rick;

Thanks for posting that link. I read it and found it nicely informative. ~ Here is what the author specified as perimeters for getting the job done;

1. Control the time the case neck will be heated.
2. Control the amount of heat delivered to the case neck.
3. Cause the case to turn at a constant rate while it is being heated so that the heat is applied evenly around the neck.
4. Prevent, or sufficiently limit, the conduction of heat into the case head
(Add to the above list the additional frills listed below, and you'll be in hog heaven
5. The annealer must be easy to set up.
6. The annealer must be simple and easy to maintain.
7. The process must be "dry" -- that is, the brass should not become wet and have to be dried before reloading.
8. The annealing process must be easy... it must not require expensive testing equipment or unusual skills and knowledge.
9. The annealing process must be fairly quick. The machine operator should be able to anneal several hundred cases per hour.
10. The process must be repeatable and predictable. Cases must be uniform from case to case, as well as from session to session.

~ I believe the method under consideration meets all these requirements except the nicety of #7 keeping the case dry, mostly for the convenience of it all.

The temperatures addressed in the piece didn't address "zinc burning" at all but did nail down how hot is too hot - namely anything in excess of about 850 F - or when the brass becomes "orange hot" ~ or hotter he might have said.. Note that I heat in dim light and nothing over dull red (barely glowing) is ever exceeded. My fingers (rotating the case in the flame to assure evenness of heating) could never stand anything hotter anyhow!

In closing let me say that the 7x57 cases that I processed have been reloaded and fired with no problems or differences being noted in their performance ~ except that none of them showed any cracks or splits in the necks (or anywhere else).

Good morning
Forrest

[doctorggg]

FAsmus,

After reading the article provided by Rick. I just did some experimenting. I had asked the question on whether you should see a real change in the color of the brass neck (#14). No one answered me. I was concerned because I was heating 7.62x39 cases to a count of 1013 or 13 seconds. No green color, no red color. I painted 475* Tempilac about 1/3 the way up the base of 3 cases. I painted 750* Tempilac on the neck and about 3 mm below the case shoulder. They were spun in a drill with two plumbers blow torches facing each other- tip to tip. Only the neck was spun in the flame. I let them cool in a pie plate rather than water drop them. The results were ideal. The neck reached 750* but not more than 1mm below the base of the neck. The white Tempilac (475*) never changed color even after cooling off. My conculsions are each type of case will require different times using the same technique. My 300 Blackout (converted 223) only take 1005 (counting 1001, 1002 etc) about 5 seconds. I believe the article when it says consistency is the key. I will no longer water drop my cases. Thank you for starting this post. I learned a great deal from it. By the way with these cases there is only a subtle change in the neck color.