That's because he fully anneals anyways which means his necks get to 900* + . There's a really cool graph I can't find anymore that shows the graduating temps and the effect on cartridge brass . It slopes downward and you can see a steady flat line until you get to 450*-ish then it starts to drop and continues to drop relatively consistently until it hits the 900 to 1k* mark where it flattens out again . So if you anneal to 900* then test if annealing to 12 or 1300* makes a difference there will be no noticeable difference in seating pressure . However if you anneal to 600* ( stress relieved but not fully annealed ) then anneal to 1200* , there will be a noticeable difference in seating pressure . However you would still likely need a fancy seating gauge to measure it . I've read human feel can only discern about a 10lb difference , under 10lbs it's likely we could not tell the difference just by feel . I actually use that train of thought to gauge if my necks are consistent . If I feel a difference in seating pressure I know I've annealed that batch very inconsistent and likely will anneal again .
Annealing Question (new member)
- Thread starter Hoyt56971
- Start date
That's because he fully anneals anyways which means his necks get to 900* + . There's a really cool graph I can't find anymore that shows the graduating temps and the effect on cartridge brass . It slopes downward and you can see a steady flat line until you get to 450*-ish then it starts to drop and continues to drop relatively consistently until it hits the 900 to 1k* mark where it flattens out again . So if you anneal to 900* then test if annealing to 12 or 1300* makes a difference there will be no noticeable difference in seating pressure . However if you anneal to 600* ( stress relieved but not fully annealed ) then anneal to 1200* , there will be a noticeable difference in seating pressure . However you would still likely need a fancy seating gauge to measure it . I've read human feel can only discern about a 10lb difference , under 10lbs it's likely we could not tell the difference just by feel . I actually use that train of thought to gauge if my necks are consistent . If I feel a difference in seating pressure I know I've annealed that batch very inconsistent and likely will anneal again .
I worked with a PHD metallurgist that was a consultant for the copper industry. He told me 1050F was red. Different degrees of red (dull, bright ect ?). 750F is just the lower end of the start of annealing. It should be a good temp to shoot for. I asked on this website who came up with 750F as the best temp. Seems like no-one knows. I anneal for short times and I'm happy with the results regardless of how much annealing is taking place. You shouldn't have to paint each case. Once you figure out time to melt just keep doing them all the same. Time may vary with torch setup.That's not accurate as it relates to cartridge brass . 450* is where brass "starts" to soften "not the temp you want to get to . It's important you know cartridge brass annealing is different then simply annealing brass .
Example , most anywhere you look the common answer to annealing brass is . Leave the brass in a heat source of 600* for 60 min and that piece of brass will be fully annealed . What isn't talked about is how large or what the total mass that piece of brass is . It's seems obvious they don't mean a small piece of 223 brass is placed in a 600* heat source for 60min but rather a large hunk/block of brass with a total mass significantly larger then any one piece of cartridge brass .
Ok now that we know annealing time is largely dependent on the size/mass of the piece you intend to anneal . The second thing that can't be ignored is that we don't want the whole piece of brass fully annealed . 1/2 to 3/4 of the lower section of cartridge brass not only should not be annealed , It actually should be harder then the upper 1/4 section ( neck and shoulder ) .
All that means you need to heat the neck and shoulder to at least 600* fast enough that no part of the lower 3/4 of the case gets past 450* where annealing ( softening ) starts .
All that said I find it inconsistent with my testing that a case in a propane torch flame for 12 seconds does not reach 450* . My test showed a 308 case in a one torch flame for 12+ sec would reach a temp of at least 900* . My guess is you either need a different nozzle or place the torch in a different place/angle to the case maybe even both to get the desired result .
Also you really should be using Tempilaq which is a temperature indicator that melts when it reaches a specific temp . You can buy it for different temps . Here's what mine looks like which is 750* inside the necks and 450* below the shoulders
rwj
Gold $$ Contributor
I don’t know that 750 F is the best, but it’s the minimum temperature that causes a significant hardness change in a relatively short time period. The rate of change is higher at 1000 F. The complete research paper from which the charts below were obtained can be found at this link…
Recrystallization Behavior of 70/30 Brass
Cartridge brass undergoes significant changes in mechanical properties as a result of cold work. These changes are effectively reversed in the annealing process returning the metal to its precold-worked state. The major goal of this study is to
www.academia.edu
Time in minutes. You need a chart with seconds. I put a chart up in seconds many times on this website with harness on case necks. We don't know the % cold work. Any reasonable time with a torch seems to work.I don’t know that 750 F is the best, but it’s the minimum temperature that causes a significant hardness change in a relatively short time period. The rate of change is higher at 1000 F. The complete research paper from which the charts below were obtained can be found at this link…
Recrystallization Behavior of 70/30 Brass
Cartridge brass undergoes significant changes in mechanical properties as a result of cold work. These changes are effectively reversed in the annealing process returning the metal to its precold-worked state. The major goal of this study is towww.academia.edu
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We don’t need a chart in seconds . Why do you suggest that ? We need to know what the mass the material in the chart above is based on , not what happens to that brass in seconds.
I’ll tell you what hsppens to that brass if only in the heat source for seconds. Only a small outer section of the matetial is annealed . While the entire inner portion will be completely uneffected .
I’ll tell you what hsppens to that brass if only in the heat source for seconds. Only a small outer section of the matetial is annealed . While the entire inner portion will be completely uneffected .
Did the PHD friend understand you were talking cartridge brass and not a large block of brass . As well as cartridge brass should only be annealed in one specific area while leaving the rest unaffected by the annealing process ?
I also built an annealing machine, an induction one. I used tempilaq etc. The effect was I added another variable to my reloading equation. And for sure induction annealing is more precise than any torch based annealing machine. In my annealed batch of brass I had more differences in neck tension than in a non-annealed batch.
If I decide to go back to annealing I will by an amp. Otherwise I will sell the brass after 7 firings and buy new one.
RegionRat
Gold $$ Contributor
Hang on a second. Let's take a step back.
The majority of charts you see in metallurgical books on brass alloys are for a puck. It literally looks like a little 1/4" thick disc, like a little hockey puck. It needs to be easy to prepare for microscopy to study the grain size, and to be ready for hardness tests.
Many types of handy samples have to do with other common tests that have nothing to do with making cartridge cases, but are used for proving the quality controls of the alloy are met. Those samples are not useful for proving what happens to a cartridge case during manufacture or to reloading.
Not to start an argument or debate, but yes we do actually care about seconds, not hours or even minutes.
We don't want to soak a cartridge case and ruin the case head or body, but we do need do three things to keep this under control. 1) Heat Flux Rate, 2) Peak Temperature, 3) Time.
First, we have to do this at the neck and it can go down past the shoulder, but should not affect the body. That means we don't have a lot of time to get the neck into annealing temps before the heat would go down the body. So, the heat flux rate has to meet some minimums and also meet some temperatures that can work fast.
Yes, than means we are in that 750 neighborhood or higher if we want to get the annealing done within seconds. If we go very much higher, we start to oxidize the alloys, and you will see the zinc oxides start to surface. If we take too long, the shoulders and body get softer than we want.
We don't have many great options for measuring transient temperatures. The human eye can begin to see the infrared heat when the brass jut happens to get to near 750, which is a useful temperature cause it only takes a heartbeat at or above that temp to get to our goals. All of the time above about 400 counts, but the higher temps count for much more as the temp gets closer to or above 750. If you happened to hit 1000 it isn't the end of the world as long as you didn't stay there for more than a blink. Any higher or longer and you will over anneal, which again isn't instant death but would be a reject on a production line.
To anneal at home, you need to be able to find that initial glow point. It helps to avoid heating so fast that you go right past it. With a flame, I would rather call it to within 0.1 seconds on a 7 second rate, than call it to 0.1 seconds on a 3 second rate and have it climb so fast it overshoots. You will get much tighter results with the 7 second heat flux rate since you can be off just a little without over or undershooting. You also don't want to go so slow that the case body starts to soften.
For most metals with a typical emissivity, these are rough values in degrees F, but as you can surmise they are as good as Tempilaq.
750 -- Red heat, dull glow just visible in the dark
885 -- Red heat, visible in the low light (gas flame is dimmer that this, but brighter than dark)
975 -- Red heat, visible in room light
1100 - Red heat, visible in direct sunlight
1300 - Dark red
1500 - Dull cherry-red
1650 - Cherry-red
1800 - Bright cherry-red
2000 - Orange-red
We have used all sorts of methods to anneal in production, and at home. You can hit the numbers with a flame, or using induction. Spotting a dull glow in a darkened room with the torch should put you between 750 and 885 F.
Depending on the thickness of the brass and case size, it just takes a moment at those temps to get the hardness value down below 120. It takes actual HV testing to know the exact amount of time at, above, or below that glow point to hit the perfect value. Good annealing doesn't have to be an exact value but a consistent one below 120 will meet the goals.
The goals of cartridge brass annealing look something like this. We try to stay in between the lines. Cases don't explode if we are off a little, but the whole idea here in this context is to try and get it right.
Keeping the HV inside those lines just means you will look more like the virgin brass. A little higher or lower is okay, but the idea is to make it consistent for seating and tension. It will typically fall inside those lines when the heat flux rate, max temp, and time to temp, are good.
If you are not disciplined about the heat flux rate, the peak temp, or the time, you are better off not doing this at all. You can send your samples to a lab for testing, or you can compare your annealing to virgin brass in rough terms by seating force.
Slide prep and hardness surveys are not cheap, so if you can't handle the discipline of annealing, you can live without it. As is often the case with reloading.... YMMV
That was exactly my point , clearly I could have done a better job writing it . Although I have said several times annealing cartridge brass is not the same as simply annealing a hunk/puck size piece of brass .
My point was as you pointed out . just about all charts and or papers I can find use a large hunk of brass in a heat source at a very specific temp for a long period of time . Why do we need to know what seconds of annealing does to "that same" large puck size piece of brass , we are not annealing a large piece of brass . The answers are the same for a puck of brass as it is a small section of cartridge brass ., because the answer is based on temp reached not how long the material was exposed . The reason they use 1hr is to ensure the entirety of the material reaches the desired temp . Ever cook a casserole ? I can place my 3700* MAPP gas torch under the pan for one minute and I promise you the casserole won't be done . Maybe the section I applied the torch would be burnt but the farther you get away from that spot the less cooked the casserole will be .
This is about getting the material to reach a specific temperature not how long it's exposed to the heat source . After we understand that we can talk about how long it needs to be in the heat source .
Example using same size case and reaching the same temp . ( generalizing the times ) to emphasize the point
One torch as the case spins about 6 or 7 seconds
Two torches at apposing angles as the case spins 3 or 4 seconds
AMP machine about 1 second
If time is the main importance how are these all reaching the same temp at different durations of time in heat source . You first need to know the size of the material and the temperature of the heat source . It is only then can you quantify the time needed to anneal . You can't do it the other way around , grab a random hunk of brass and put that in a salt bath of a random temp for 2 seconds and call it annealed because it was in the bath the time you wanted . Timing is the last thing you figure out in cartridge brass annealing not the first . The AMP machines prove this , at least I think they do . Don't you enter a program number that indicates the size of brass you plan to anneal first . Then place that case in the machine and it actually ruins the case to determine the time need to be in the heat source . The AMP does not start out with , we'll heat the case for 2sec then work backwards from there to figure out what the temp of the heat source needs to be and the size case needed .
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RegionRat
Gold $$ Contributor
Agree Metal God.
The controls of any of the annealing methods are the heat flux (rate), the peak temp, and the process time.
The indirect goals are often run blind, meaning most folks never check grain size or hardness values.
I had the benefit of closed loop learning with slides and hardness values. At home, we don't typically have those.
You are either taught by someone with expertise, or you play with your process controls and test with seating force or just look at your targets.
It is just as easy to have no benefit in terms of accuracy or brass life, as it is to get this right. There are lots of folks who take this up and quit it because they made things worse. It isn't for everybody.
The controls of any of the annealing methods are the heat flux (rate), the peak temp, and the process time.
The indirect goals are often run blind, meaning most folks never check grain size or hardness values.
I had the benefit of closed loop learning with slides and hardness values. At home, we don't typically have those.
You are either taught by someone with expertise, or you play with your process controls and test with seating force or just look at your targets.
It is just as easy to have no benefit in terms of accuracy or brass life, as it is to get this right. There are lots of folks who take this up and quit it because they made things worse. It isn't for everybody.
rwj
Gold $$ Contributor
Please provide/cite your sources. The amount of cold work can be calculated based on the before/after case sizing dimensions. I’m satisfied with my annealing results too.
I thought it was simple to understand METAL God.
Good evening to all and Merry Christmas
I have been able to get back to this, purchased tempilaq in 450 and 750. Torch is a pencil tip, and did some adjustments To torch angle and position.
with the tempilaq, the case is run through the flame for approximately 4.5 seconds at which point the 750 reacts and the 450 down on the case body is unchanged.
shut off the lights and ran again in same fashion, very slight red with the lights off.
so thanks to all who replied, the tempilac was the key I needed as I can setup and run a couple of cases and verify the times are running properly and I am getting into the correct range. Merry Christmas and happy holidays to all.
750 degrees a pointless number from some unknown internet source, your brass will never be annealed
in 4.5 seconds at 750 degrees. For brass to be fully annealed at 750 degrees it would need
to stay at 750 degrees for an HOUR.
in 4.5 seconds at 750 degrees. For brass to be fully annealed at 750 degrees it would need
to stay at 750 degrees for an HOUR.
Reese has some very good information regarding annealing. Unless you have access to a Vickers hardness tester or the ability to analyze brass via a microscope, some of what has been posted on this thread seems to be fairly arbitrary. I changed to an Annie induction annealer and tossed the Tempilaque that came with it after seeing Reese's video's. There's a member on this site who has access to Vickers testing in a lab. He was telling me he has to induction anneal his 6ppc brass to almost 1200 degrees for a proper anneal. You can also read on AMP's website regarding their research and testing. Not too different from Reese's info...
That annealing is WAYYY TOOOO FAR down the body of the case. Should be 1/8-1/4” max into the case body.
dave
You guys “think” you’re all that and a bag a chips . There is in fact stages of annealing and VERY good reasons for it . It’s not an all or nothing proposition as some might believe . It appears some here can’t see the forest through the trees . Any of you expersts anneal your AR10 cases to 1200 degrees ? No - Didn’t think so cus you’d have to little bullet hold and jam the bullet into the case as it’s chamberd . Grain structure starts to change somewhere around 500* and 750* to 800* is perfect to relieve stress of very thin sheets of brass like cartridge case walls while still leaving some work hardening in the necks for more bullet hold . This reduces the possibility of bullet set back on aggressive auto loaders while also allowing for more reloads per case before necks start splitting/cracking . In these types of rifles you are not looking for “perfectly” prepped cases because they are so hard on cases in the first place . Generally when annealing auto loading cases you are looking to stress relieve to get a few more reloads out of the cases rather then bench rest quality case prep .
Just because you know one thing and know it well doesn’t mean you know everything!
Just because you know one thing and know it well doesn’t mean you know everything!
drop_point
Silver $$ Contributor
All I know is I anneal until I get a dull red in a dark room for the mouth of the case. This typically occurs in 3.5s-5.5s on my Benchsource depending on brand and cartridge.
I do not get brittle brass, I do not get split necks, I do not get set-back in my .308 semi-auto or my 5.56s. On my bolt guns I get good precision, low ES/SD, and I've got .260 Rem brass with Rem head stamp that I've fired over 15x and .308 Lapua brass that has been fired close to 20x. Whatever I'm doing is working!
I do not get brittle brass, I do not get split necks, I do not get set-back in my .308 semi-auto or my 5.56s. On my bolt guns I get good precision, low ES/SD, and I've got .260 Rem brass with Rem head stamp that I've fired over 15x and .308 Lapua brass that has been fired close to 20x. Whatever I'm doing is working!
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