Over Annealing ?

[Old Navy]

Can you ruin brass by over heating the neck?

This is what the brass looks like. I have tried every chemical and even Brasso to remove it. Nothing will touch it. The brass is Peterson 6XC necked down to .22XC. I just resized a few cases down using a .010 smaller bushing than the loaded neck OD. Feels the same as .003 smaller when seating the bullets.

 

[Webster]

Can you ruin brass by over heating the neck?

Everyone probably has a different definition of overheating. I used to squeeze the necks gently with a pair of pliers and see how easy they get slightly oval compared to an unannealed case. I anneal till definite red for about 1 sec. with a torch. The necks always had stiffness compared to an unannealed case. If you size the necks , then expand with a mandrel several times they will get harder. I always thought I would shoot to see if there is a difference. How fussy you get might depend on what the rifle is used for, hunting or serious competition. It's a lot more difficult to get the necks too soft than you think with a torch. I think they would have to be red for over 5 seconds to start getting soft. . If they are really soft you can squeeze the necks a little oval with your fingers.

 

[RegionRat]

Can you ruin brass by over heating the neck?

Yes, you can take it too hot for too long and it goes lower and lower in HV which also correlates to the other material properties.

 

[Straightshooter1]

Can you ruin brass by over heating the neck?

Hmmm??? It depends on what you define as "ruin" or "over heating". . .???

You can heat the neck to where it has absolutely no spring back or holding force and not do that to the rest of the case (like down the body to the web), which depends on how fast the neck is brought that state. A dead soft neck would not be good as it would not have the spring back to allow the case to be ejected (it'd get stuck).

Always gotta keep in mind that the annealing isn't just about the amount of heat, but also the amount of time. Like the AMP testing to get the proper code will melt the neck and even the shoulder and still not "ruin" the other part of the case. It takes time for the heat to make it's way down from the neck to the base when the heat source if focused just on the neck or neck-shoulder junction. If one is getting the neck to 1,200°F for a fraction of a second or even a full second, that's not enough time to get the body of the case to that temperature, yet the neck will have gotten enough heat and time to soften to just about right, not making it dead soft, and the rest of the case will be just fine.

Enough heat for too long not only can cause the neck to lose its spring back, but the body can also lose its springback. . . . . yeah, it'd be ruined and you definitely wouldn't want to try firing it. It could not only not spring back, it could rupture.

 

[Webster]

Can you ruin brass by over heating the neck?

My annealing study results. About the tenth time I put this chart on the website.
6BR Lapua case necks in a lab quality furnace for 15 seconds and 5 minutes. I used 15 seconds because I didn't know how long it would take to reach temp. If the necks don't soften much in 15 seconds at 1000F constant temp they should only lose a couple hardness units flash annealing at 1000F peak temp.

Dead soft can happen for 5 minutes at 800F constant temp. A knoop hardness number of 32 a true dead soft took 5 minutes at a constant 1200F.

The University of Illinois published an annealing study that shows the same results and I put their charts on this website several times.

 

[243winxb]

yes. Zinc gets burnt out, leaving just soft copper.

Can you ruin brass by over heating the neck?

 

[dantiff2]

Ruin? No.. UNLESS you get the case head too hot.
When I first started to anneal, I did as everyone else and just got the mouth a very light hint of red in a dark room. That worked fine and the results showed perfect shoulder bump and bullet seating force from then on. Curiosity got to me, so as my batch of Norma BR brass was coming to the end of it's life, I took a handful and made them glow bright orange, ( glowing!) and the brass looked black in the daylight. I fired those brass as sighters at my local 200 yard club match and those brass shot into the same group as my normal loads/ annealing. After that point, I no longer had any worry about getting a case a little hot.
Dan

 

[Krogen]

yes. Zinc gets burnt out, leaving just soft copper.

That's an "old wives tale." The case is an alloy. Zinc isn't going to burn out of the metal at the molecular level.

 

[Tesoro]

When your cleaned used Lapua brass comes close to matching new Lapua brass then you are doing it right! It takes a bit more than the dark cherry inside the neck to get it to resemble factory.

 

[ELR LVR]

yes. Zinc gets burnt out, leaving just soft copper.

Thats about the only way I know too
Disassociating the zinc from the copper
The zinc will burn
and you basically no longer have brass
----------------------------------------------
Kind of like you can't really cant hurt Stainless with heat, unless you REALLY overdo it and "sugar it" and disassociate the chrome from the nickel and the etc from the etc and THEN it is no longer stainless

 

[ELR LVR]

That's an "old wives tale." The case is an alloy. Zinc isn't going to burn out of the metal at the molecular level.

If you use an Oxy/Acetylene torch it will
Same thing that happens when you take a torch to Galvanized metal
the Zinc burns out and leaves behind a white powdery film
--------------------
Never seen this happen with a propane torch though
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If you ever try TIG welding brass thinking zinc will not burn out, just because it's being shielded by a Noble Gas......get back to us on how that worked out

Boiling point of Copper is 2562°C.
Boiling point of Zinc = 907 C
When you get it hot enough for the zinc to boil and the copper doesn't
It's no longer an alloy
When metals boil, they act the same way as water does when it boils
It's not just melted, It's boiling and bubbling and bouncing and of course when it does that more surface area is being exposed to O2 so then oxygen is reacting with it accelerating the reaction going on and so on.
------------------
I found this out when i used to melt down gold into ingots/ buttons ......Gold boils too
Found out quickly why you want flux on top, so ya don't loose your gold from it boiling and bubbling and bouncing all over the floor everywhere
If you let your gold boil it does make a much more interesting more natural looking nugget though
Likely exactly what happens in nature in certain conditions via hot steam

 

[Tesoro]

907 C = 1600 F

 

[ELR LVR]

907 C = 1600 F

True statement (1.8*X+32) = F
So my point being, unless a guy is using an Oxy/Acetylene torch.............kinda hard to do

 

[243winxb]

That's an "old wives tale." The case is an alloy. Zinc isn't going to burn out of the metal at the molecular level.

Better safe then sorry.
Google-
Is brass toxic when heated?

Yes, brass can be toxic when heated to high temperatures, specifically when the zinc it contains vaporizes. Zinc fumes can cause respiratory distress and a condition called metal fume fever if you're exposed to high enough concentrations. Copper, on the other hand, has a much higher boiling point and is unlikely to vaporize during typical torch work.

Personally, i have no idea, If true?

 

[ELR LVR]

Better safe then sorry.
Google-
Is brass toxic when heated?

Yes, brass can be toxic when heated to high temperatures, specifically when the zinc it contains vaporizes. Zinc fumes can cause respiratory distress and a condition called metal fume fever if you're exposed to high enough concentrations. Copper, on the other hand, has a much higher boiling point and is unlikely to vaporize during typical torch work.

Personally, i have no idea, If true?

Thats correct,
When I was in the welding business we had to be cautious of welding on Galvanized steel
due to the ZINC fumes
Zinc in brass will do the same thing

 

[divingin]

Galvanized is a zinc coating. Completely different from something alloyed with zinc.



From AMP (under the "Our Research" tab, "Annealing under the microscope, Part 1" article):

The basics of cartridge brass:
[Note: I deleted the first entry -Windows renumbered items starting from 1]

1. Cartridge brass melts at 915°C (1679°F). Up to that temperature it remains homogeneous (Appendix 1 - 1.1).
2. Dezincification of brass can occur because of chemical attack, but heating brass, even to high annealing temperatures cannot cause dezincification unless chemicals are present. The zinc content of the alloy cannot burn or melt out up until boiling point (Appendix 1 - 1.6).

 

[Doom]

In the event the neck is over annealed (dead soft), a full length sizing die (non bushing) and expander can be used to work the neck and harden it by running the case through multiple sizings.

If the body of the case has been softened its best to trash the case as there is no convenient way to work harden it.

 

[Webster]

Thats about the only way I know too
Disassociating the zinc from the copper
The zinc will burn
and you basically no longer have brass
----------------------------------------------
Kind of like you can't really cant hurt Stainless with heat, unless you REALLY overdo it and "sugar it" and disassociate the chrome from the nickel and the etc from the etc and THEN it is no longer stainless

The boiling temp is the boiling temp of the alloy not the boiling temp of copper or zinc. The brass will melt long before you reach a boiling temp.

 

[Rat Rifle]

When your cleaned used Lapua brass comes close to matching new Lapua brass then you are doing it right! It takes a bit more than the dark cherry inside the neck to get it to resemble factory.

I have chosen You to pick on nc . I don’t clean My brass. I keep My 308 Win brass in the flame 10 secs, and My 260 Rem in 8 or 9 secs., and they both get the pleasant glow. But My 6 BR and 6 BRA Lapua Brass DO NOT GLOW, no matter how long I leave them in the flame. A color change occurs 1/8” below the shoulder, so I am at least doing that. I am among the group that is told We are not annealing, rather stress relieving. That’s OK because what I’m doing is working for Me. I leave My 6 BR and 6 BRA Brass in the flame for 6 seconds. If I understand the postings in this thread, I could go 7 seconds?, 8 seconds?, 9 seconds?, 10 seconds???. Would more time show benefit on target. I know, I have to test and see for myself, but like I said, I’m happy the way things are?

By the way, what color are the case necks when they’re in the AMP Machine ?

 

[Tesoro]

All I know is generally the less you mess with stuff the more consistent your shooting! Many put too much emphasis on things that are overridden by field skills . However for moi, who dosent compete then I can pick my days and the extra attention to uniformity can help, probably more mentally than anything else.

I spin the outside with some 3m to clean them up but never tumble as the carboned inside of necks are precious to me.
It is all in the angle of the flame, where it is positioned, and how much it heats up the neck vs the shoulder. Obviously longer necks vs shorter necks need different positions. Diff brass needs diff times.
A good way to test your annealing is to measure shoulder with comparator after bumping and then a few days later. If annealed correctly, imo, the 2 day aged brass will have grown a tad. So need to adjust die accordingly. That is of course if you are looking for a classic BR fit.
Never used electric to do brass, but it seems like it would produce the most uniform if used with a machine and timer.