Annealing- is it 475 degrees or 750 ???

[easternncnative]

After experimenting with annealing a bunch of throwaway 308 brass, I've come to the conclusion that I don't know what the hell I'm doing. Furthermore, the more I read, the more confused I am. Some sources state that case necks have to go to 750F while Hornady's annealing kit includes temp indicator paste at the 475F level. Which is right? And then, there are the color descriptions- I find myself wondering whether that was really dull red or did it go to bright red....or perhaps mauve.

The bottom line is that I don't want to screw up my Lapua brass, many of which are now into their 5th & 6th loadings.

I know that this topic has been hashed & rehashed here but if someone could help me out with the details, I'd be greatful.

Like maybe something like....hold the rotating case in the blue flame and count to six and you're done or something like that.

Thanks for any advice.

 

[doubled]

Re: Annealing- is it 475 degrees or 750 ???

I put 750 paint inside the necks and 450 down the case. if i liquefy the 750 and the 450 stays intact just below the shoulder I call it good.

I takes me about 8 seconds per case with a single torch in a giraud annealer.

 

[Guest]

Re: Annealing- is it 475 degrees or 750 ???

Semi dark room,(Propane sucks) oxy/acetylene or MAP gas at the least, point of flame at the datum. Just as you start to see the red glow drop the slut in water, an spin up another. 100 (+ -) rpm works best for me.

Attach your drill to a 1 X 4 thats attached to a door hinge with a up right stop, thats bolted or clamped to a table, bench, ect. Fix a device for the drill trigger, (mines adjustable via a screw).
Now fix a rig that holds your torch at the proper place on the case neck with the drill rig up. Set your bucket, pan, washtub, whatever, to catch the falling case.
For .308 a short 9/16 deep well, 3/8" drive socket with a 1/4" bolt that's bolted to the socket an held in the drill chuck, works well. Change sockets for different cal's.

Think out of the box, don't support the tax base. That's the only thing they understand.

 

[TexIndian]

Re: Annealing- is it 475 degrees or 750 ???

What doubled said about temps. HERE'S a link that should help.

 

[doubled]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gunfighter14e2</div><div class="ubbcode-body">Semi dark room,(Propane sucks) oxy/acetylene or MAP gas at the least, point of flame at the datum. <span style="font-weight: bold">Just as you start to see the red glow drop the slut in water</span>, an spin up another. 100 (+ -) rpm works best for me.
</div></div>

at that point you are over annealed. check the spring back of the neck with some pliers and you will find the metal has become to soft which is dangerous.

 

[Guest]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: doubled</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gunfighter14e2</div><div class="ubbcode-body">Semi dark room,(Propane sucks) oxy/acetylene or MAP gas at the least, point of flame at the datum. <span style="font-weight: bold">Just as you start to see the red glow drop the slut in water</span>, an spin up another. 100 (+ -) rpm works best for me.
</div></div>

at that point you are over annealed. check the spring back of the neck with some pliers and you will find the metal has become to soft which is dangerous. </div></div>
I must live right because, it's worked for over 45+ years?

 

[coues7]

Re: Annealing- is it 475 degrees or 750 ???

Girauds instructions definitely differ from others......

 

[bigwheeler]

Re: Annealing- is it 475 degrees or 750 ???

It's temp and time at temp. Plenty of info on the net outside of gun forums. Quenching does nothing more than cool it off quicker, it does not help or hurt the annealing process. I have found as soon as the neck begins to glow in a blacked out
room (other than propane or map torch light) it's annealed. I squeeze the neck in
my calipers .002" and want full spring back. If I have to pinch with too much effort
it's not annealed enough. That's just based on experience. The new machines are
a game changer. More consistency, less time, money well spent.

 

[Teggy1]

Re: Annealing- is it 475 degrees or 750 ???

I started trying it with the 750 inside the neck, 650 on and just below the shoulder, and <span style="text-decoration: line-through">450</span>475 a half inch or so down from the neck.

Honestly, the shit I put in the neck, and on the shoulder burned off, and seemed to be inaccurate. It wasn't until I started with the <span style="text-decoration: line-through">450</span>475 deg. paint on the case body (Hornady procedure) that I "got it right" if you will. Tempilaq in the neck, and on the case is a bitch to clean off.

Also, for some reason, my brass (Winchester) does not get the pretty colors that so many seem to get here. If, I go just a second or 2 longer than when the <span style="text-decoration: line-through">450</span> 475 paint BEGINS to melt, I get a very faint rose color to the brass. Perhaps I am not annealing enough, or maybe it is the case polish preventing oxidation (which is what coloring is), I don't know. But there is a noticeable difference in bullet seating effort and the feel of the next sizing operation (after being fired again), coupled with really good brass life that leads me to believe I am doing something right.

Good luck!

 

[High Binder]

Re: Annealing- is it 475 degrees or 750 ???

Temp is only one factor in annealing metals, time is the other. You can anneal brass at 500 just the same as at 750 or higher it's just a matter of the time at that temp. Now brass being a thin relatively good conductor will xfer heat to the body/web which acts as a heat sink and you don't want to do that so the higher temp is preferable as the time at annealing temp is only seconds at 750 whereas your looking at least an hour at 500 which would ruin the body/web. I could go on and on but you get the point, a propane torch will do the job and you don't need any temp paints or any of that, just heat the low-neck/high-shoulder area in a dark room and stop when the neck turns a dark red, if you go maraschino cherry color it's ruined. I put my cases in a deep-socket attached to a screwdriver with 2 blow torches and drop them into a dry towel, takes about 7-8 seconds from start to finish.

 

[Wheres-Waldo]

Re: Annealing- is it 475 degrees or 750 ???

I have read that if they glow even in the slightest inkling...they have been over-annealed. Your best bet is to get some temp. indicating crayons or paint to eliminate the guess work.

At what temp. brass begins to glow, its over-annealed, reguardless of the time it spends at that temp. Plain and simple.

Lets look at the BR croud, as they are the most prominent annealers. I would concider 6mmBR a WELL respected BR community... so lets take what they have to say with value.

From 6mmBR's "The Art of Annealing"
http://www.6mmbr.com/annealing.html

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">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</div></div>

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">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.</div></div>

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">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.</div></div>

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">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. <span style="font-weight: bold"><span style="color: #FF0000">A higher temperature, say from 750 to 800 degrees, will do the same job in a few seconds.</span></span> If brass is allowed to reach temperatures higher than this (regardless of the time), it will be made irretrievably and irrevocably too soft.</div></div>

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"><span style="font-weight: bold"><span style="color: #FF0000">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.</span></span></div></div>

As fas as the color, I dont concider it of much indication of properly annealed brass. Ive heard that some brass does it more that other brass. That it will develope over a time period of a few monthes if the brass is left alone...ect....ect...

I did an experiment in which to see if clenliness of the brass effected color development. I untrasonic cleaned my lot of cases for 16 minutes (4 times what I normaly use) then tumbled for 24 hours (about 2 times what I normaly use) then only handled the brass with latex gloves on. The color was more distinguishable, but not by a large margin, only evident under inspection from a few inches.

 

[SPAK]

Re: Annealing- is it 475 degrees or 750 ???

I do my cases in a dark room as well. Propane torch and drill.

What I actually look for is the color change in the blue flame. I turn up the heat prety high. More intensity, less total time in the flame. As soon as I see the slightest hint of orange in the flame, I drop the case.

I found that trying to find the color change on the brass neck in the dark with the blue flame going took too long and I would go past the time that I really needed.

I've spent days trying to find the best combination of time and strength of flame and this seems to work best for me.

Basically I measured the outside diameter after sizing the annealed brass. When I found the right combination of heat and time my annealed brass outside neck diameter measured the same as a brand new Lapua case that's been expanded and resized.

If it wasn't annealed enough, the OD of the neck would be larger than the lapua case. If it was over annealed the OD of the neck would be smaller than the lapua case.

During all the testing I used a 450 tempil stick on the case body just to make sure I wasn't getting the case head too hot.

An annealing machine would be great. It would make it much easier. For now this is what has worked for me.

 

[gilream]

Re: Annealing- is it 475 degrees or 750 ???

@Wheres-Waldo...I'm a new member here and am going to attempt to anneal my 7MM Rem Magnum cases as soon as the 750 Tempilaq arrives in a few days. I have read and re-read several articles concerning annealing and one of the best of which you have referenced here. Your last quote (in all red) has always struck me as being counter to the earier part of his article. "If the temp reaches 950 degrees or even 200 degrees below that...the damage has been done...." Is he dismissing the statement that he made just a few sentences before in that 750-800 for a few seconds will get the job done correctly? He seems to contradict his own statement. Am I missing something?

 

[High Binder]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RHobbs</div><div class="ubbcode-body"> @Wheres-Waldo...I'm a new member here and am going to attempt to anneal my 7MM Rem Magnum cases as soon as the 750 Tempilaq arrives in a few days. I have read and re-read several articles concerning annealing and one of the best of which you have referenced here. Your last quote (in all red) has always struck me as being counter to the earier part of his article. "If the temp reaches 950 degrees or even 200 degrees below that...the damage has been done...." Is he dismissing the statement that he made just a few sentences before in that 750-800 for a few seconds will get the job done correctly? He seems to contradict his own statement. Am I missing something? </div></div>

No you're not missing anything. The author just doesn't fully understand the process and is confused. For example: You could anneal brass at 2000 degrees but the trick would be bringing the brass up to that temp and then bringing it back down to a safe level all within nanoseconds. Annealing is as much a function of temp as it is time. Read my previous post in this thread for an explanation.

 

[bigwheeler]

Re: Annealing- is it 475 degrees or 750 ???

I pretty much agree with most of what's been said. Orange glow is way past
ruined. The faintest maroon color in a blacked out room it's done. Brass at 2000 degrees for any length of time is toast. I think anything over 800 and it's been
done in for shooting purposes. Plenty of range brass to practice on out there.
Don't ruin your good stuff trying to learn.

 

[Wheres-Waldo]

Re: Annealing- is it 475 degrees or 750 ???

I dont think he is confused. Granted 150 F* isnt technically a FEW hundred degrees...but I get what he is saying.

 

[CanPopper]

Re: Annealing- is it 475 degrees or 750 ???

Eh...I got fed up with all this disinformation that I actually went and purchased a high temperature furnace thermometer to measure the heat of different flames.

The heat on my alcohol lamp came out to about 900 degrees F. When I tried to anneal my brass with it, it took freaking forever. Then I tried the propane torch at a lower setting. That came out to 1200 degrees F. That actually annealed the cases but you got to watch the duration.

So ignore all this bull and watch the brass instead. When you put the mouth of the brass into the flame, about 5 to 6 seconds later you will see it changing color. The color will move down the body of the case towards the head. When you see that bluish hued color moving down the brass, you are done. Don't let it creep down too far.

I take things one step farther by annealing using the aluminum loading blocks sold by one of the Hide vendors here. I find the aluminum block very effective at wicking heat off to protect the head of the brass. When I chill the loading block with ice while annealing the case mouth, I get a nice Lapua type annealing effect that doesn't creep down the body of the brass.

 

[salty dog]

Re: Annealing- is it 475 degrees or 750 ???

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1270259#Post1270259
I ve been using this method. I think its like what can popper said above with a pic.

 

[High Binder]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bigwheeler</div><div class="ubbcode-body"> Brass at 2000 degrees for any length of time is toast. I think anything over 800 and it's been
done in for shooting purposes.</div></div>

Nope: As I said above
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: High Binder</div><div class="ubbcode-body">
For example: You could anneal brass at 2000 degrees but the trick would be bringing the brass up to that temp and then bringing it back down to a safe level all within nanoseconds. Annealing is as much a function of temp as it is time. </div></div>

You can safely anneal at temps over your 800 degree mark but again the time at temp and getting to and from temp is dramatically decreased, you have to bring it up to temp and back down very quickly i.e. microseconds. The problem here becomes the quench cycle which really screws up the boundaries of the crystals.

However, no home user has the ability to do that even with the best induction heat treating equipment but the science is factual and you can anneal at way higher temps but the time is dramatically reduced to non-practical levels. Again: Annealing is as much a function of temp as it is time.

 

[High Binder]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Wheres-Waldo</div><div class="ubbcode-body">I dont think he is confused. Granted 150 F* isnt technically a FEW hundred degrees...but I get what he is saying. </div></div>

He may not be confused but he's confusing the issue because he doesn't take into account the all too significant factor of 'time'. It's not that what he's saying is wrong it just isn't illustrating the whole story to the readers. In other words annealing is comprised of a <span style="text-decoration: underline">temperature factor </span>and a <span style="text-decoration: underline">time factor</span>. It's good enough for 'Joe Blow' reader/annealer who has little/no scientific background and/or doesn't care but to really understand what's happening you need the whole story, i.e. time & temp.

A joking/serious example for the confused:

400 degrees + hours = annealed
500 degrees + minutes = annealed
800 degrees + seconds = annealed
1000 degrees + microseconds = annealed
2000 degrees + nanoseconds = annealed
10,000 degrees + picosecond = sublimation

 

[Teggy1]

Re: Annealing- is it 475 degrees or 750 ???

I think people are misunderstanding there is a difference in source temperature, and workpiece temperature.

Because you are using a heat source, say a propane torch at aprox. 4000 degrees F, significantly higher than your intended work piece temperature, is the reason it only takes seconds to achieve your 850 deg. (or whatever) target.

High binder is right, in the sense, your heat source could be 10,000 degrees and applied for picoseconds. NOT that you would want your workpiece at 10,000 degrees for any length of time.

 

[High Binder]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Teggy1</div><div class="ubbcode-body">I think people are misunderstanding there is a difference in source temperature, and workpiece temperature.

High binder is right, in the sense, your heat source could be 10,000 degrees and applied for picoseconds. NOT that you would want your workpiece at 10,000 degrees for any length of time. </div></div>

Teggy, you're right in the sense that there is a significant difference in "source temp" vs. "workpiece temp" but I and everyone else is talking about the actual workpiece temp.

The science is sound, annealing has a time component that has to be factored. 1000+ degree (workpiece temp) will anneal brass, it's just a question of how much time it takes to get it to that temp and back down and the home/average annealer does not have the capability of doing that quickly enough to not ruin the brass but just because the average user can't do it, doesn't mean the science is invalid.

 

[Teggy1]

Re: Annealing- is it 475 degrees or 750 ???

I guess, I am trying to say that IF you had a 10,000 or 100,000 degree heat source, wouldn't the thermal conductivity of the material, inhibit the ability to achieve a material temperature above the meting point, or the vaporization point before it deteriorated?

I guess I am asking, if, your material reaches an actual 10000 deg. F, wouldn't the outer surface of the material vaporize (whatever the temperature is?) before the material actually reached that point, regardless of the time it was at 10,000?

I don't think I am conveying what I am thinking, or asking very well.

 

[High Binder]

Re: Annealing- is it 475 degrees or 750 ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Teggy1</div><div class="ubbcode-body">I guess, I am trying to say that IF you had a 10,000 or 100,000 degree heat source, wouldn't the thermal conductivity of the material, inhibit the ability to achieve a material temperature above the meting point, or the vaporization point before it deteriorated?

I guess I am asking, if, your material reaches an actual 10000 deg. F, wouldn't the outer surface of the material vaporize (whatever the temperature is?) before the material actually reached that point, regardless of the time it was at 10,000?

I don't think I am conveying what I am thinking, or asking very well. </div></div>

Nope I fully understand what you're saying which is why I said:

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: High Binder</div><div class="ubbcode-body">A joking/serious example for the confused:
10,000 degrees + picosecond = sublimation </div></div>

Sublimation is the science/engineering term for what you said but in one word, instead of a paragraph.

 

[magnum_99]

Re: Annealing- is it 475 degrees or 750 ???

Tempilaq 750 on the outside and inside of the case neck indicates that the surface is reaching 750F at about 6 seconds (3/4" propane flame length with case head in tip of flame). I hold it another 1 second to ensure the brass has fully reached about 800F through the neck then I remove from the flame. It seems to work.