Annealing: Specific Heat Question

[MagnumManiac]

This temp question is perplexing at best.
It must be understood that it takes temp AND time.
Annealing is the process of changing the brass crystals through heat for a specific amount of time.
When I anneal, I get an orange to pink hue when the brass is the correct temp, no red glow of the neck at all and 2 seconds at this point has the neck annealed.
The temp of the flame is way hotter than what is required, so the TIME is what is being regulated here.

Cheers.

 

[Stonyman88]

I anneal until the very tip of the neck turns red. I use the Annealeez and most cases are in the flame between 4 and 6 seconds.

I agree and do the same if I understand you, point my flame right at the shoulder, when it turns red it drops out and moves on. I also have about 4-5 seconds in the flame.

 

[Stonyman88]

It's not rocked science guys, a good video is Erik Cortina on the tube. I point the tip of the flame at the shoulder, when it turns red it's done, the color changes about 1/4" below the shoulder and I get many many reloads from them, some over 10-12 + to get the 650 temp isn't hard, if it gets to hot it wild be like rubber kinda., watch Cortina's video and you'll understand much more.

 

[6MM06AI]

I ordered the Mark 2 amp anneal er a few days ago and it's really awesome! It will anneal a case is seconds. Wasn't cheap but worth the money I spent on it

 

[BrentM]

I do the dark room and when I see the first sign of the neck start to glow a faint amount it's done. I built an induction annealer and can control time too .1 of second. So far very happy with the results. The photo with 2 cases is a freshly cleaned one and one that has been sitting around for a year. Case color isn't a good indicator of annealed but it shows the consistency imho

 

[Another Casual]

I don't own an AMP (and likely never will as I'm too cheap for their asking price), but their website is full of helpful data.

Induction Annealing Brass | Our Research | AMP

View the latest articles from AMP Annealing. Get tips and tricks from our R&D. Here we upload articles to provide your the best possible information on innovations in the annealing process.

www.ampannealing.com

I'm going to point you to this article specifically which has a chart showing temperature over 10 seconds when flash annealing a neck. Seems to top out around 1025. Take from that what you will.

They also have an article about "salt bath annealing" with real hardness data to back up what you think is happening vs what's happening.

Every annealing thread immediately goes off the rails. I'm not an expert, so I look to the experts and are what data they've produced from testing. Food for thought.

 

[Mike Matteson]

Tempilac wasn't much help for me and I believe I under-annealed trying to
use it. It turns black and it's messy. I was overthinking it and i get excellent results without trying to get too scientific. Trick is to do them all the same every time. I turn the lights out and go till I see the glow And I make note of the time that it takes. I get the anneal marks I'm looking for and they don't extend lower than 1/3 of the case. For medium cases like 308 and creedmoor that takes between 7 and 11 seconds in the flame. 222 gets hot much quicker than 28 Nosler. I set the dial for the time and let it run till they all go through.

Note your time on annealing for each type of case. That way you have a record. Amazon have marking pen instead of the bottles. You can get them at different temp levels.

 

[Mikecr]

Brass does not come to you fully annealed. It's hardened an appropriate amount.
So you don't need to be fully annealing. Your goal should be grain recovery back to appropriate hardness.
Once brass reaches this recovery temperature (750F-1,000F) what we need happens very fast (within ~5 seconds). At that temp 5 seconds or 50 seconds makes no difference. You're not going to hurt anything.

But when you're applying way way higher temps, that's when you need careful timing control, to get your brass at the right temperature and no hotter. Otherwise, you'll end up with inconsistent or wrong hardness.

Where dip annealing works so well is that it immediately takes brass to the exact temperature desired. No more, no less.
The brass is heated from both inside and outside simultaneously.
There is really no timing to be concerned with. You just hand dip any cases as deep as you want. Takes about 10 seconds each.
Because heat (that is not excess) is only applied for this short period, there is little to no heat migration. I hold case heads with bare hands, and initially I dip to mid case bodies. Later I only need neck or maybe shoulder relaxing.

I haven't observed cases in the dark (I do this in the light), but there is not much temper or color change with this. Just a little shading.
More like Norma's brass appears.

 

[Mike Matteson]

following!

 

[mulie]

OK, after all that I have tried. AMP ANNEALER, split the cost with a friend or two. Yes you will cry once however as your brass changes from lot to lot and aging, so will the annealing temperature. The Amp will allow you to adjust with confidence. I have built 3 different annealers using flame. Nothing was as quick or reliable as the AMP annealer.

 

[blacktails]

I do the dark room and when I see the first sign of the neck start to glow a faint amount it's done. I built an induction annealer and can control time too .1 of second. So far very happy with the results. The photo with 2 cases is a freshly cleaned one and one that has been sitting around for a year. Case color isn't a good indicator of annealed but it shows the consistency imho

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The induction annealer sounds good. Where did you get the instructions for the one you built?

 

[VenatusDominus]

The induction annealer sounds good. Where did you get the instructions for the one you built?

I built an induction annealer for $300 with parts ordered from Amazon. There is a thread on AccurateShooter.com with instructions for simple timer controlled annealers to more complex annealers controlled with Arduino and infrared temperature sensors like the one I built. I built mine to accommodate everything from .223/5.56 to 300 Weatherby. The end of my video shows the switch between the two cartridges.

Link to thread on AccurateShooter.com:
You are being redirected...

Here is my build:

 

[nksmfamjp]

Where dip annealing works so well is that it immediately takes brass to the exact temperature desired. No more, no less.
The brass is heated from both inside and outside simultaneously.
There is really no timing to be concerned with. You just hand dip any cases as deep as you want. Takes about 10 seconds each.

Can you tell me how you have determined what the temperature of the brass is? Have you looked at the heat transfer fea model, hand equations or possibly some way to measure the internal brass temperature?

In my experience, the convective heat transfer is relatively slow across the material boundary. Also, the conduction within the same material is quite fast. I think that was what AMP was trying to show, but they couldn't measure it, so they measured hardness after annealing.

So, I ask how you know what temp your brass gets to?

 

[VenatusDominus]

But when you're applying way way higher temps, that's when you need careful timing control, to get your brass at the right temperature and no hotter. Otherwise, you'll end up with inconsistent or wrong hardness.

This is completely opposite of the established science on the subject. Is this your personal opinion or do you have something based in science that supports your conjecture?