Article: The Realities of Case Annealing

[J.Baker]

You can view the page at http://www.savageshooters.com/content.php?405-The-Realities-of-Case-Annealing

[JASmith]

Excellent discussion!

The effect of carbon build up on pull force is rather interesting.

Did I overlok the control tests? In particular, the variation of pull force between cases and from shot to shot when no annealing is done?

[RC20]

There has been an extensive discussion on this over the The Firing Line reloading site.

While complex, it also has been done with a healthy degree of scientific testing and end results.

https://thefiringline.com/forums/showthread.php?t=587448

One aspect that I have been most interested in was a fellow called Jeep Hammer and another Supercub 99 found that inductive annealing was significantly affected by clean and carboned cases. Clean took longer.

While AMP contribute discuss this, they do not say that they have a program for it or the use of one of the programs that achieves the "perfect anneal"

While good, it will under anneal and therefore is not perfect. Same brass but different dates and lots will change. So I am not in agreement with perfect. I think a tad under annealed is better by far than perfect or going over when perfect is not, which does ruin the brass for spring back.

There is also the aspect of cross comparison using Hardness as the control factor. While that is probably fine for a given batch, the in depth assessment is what is accurate.

I also question the carbon issue, when I have done my Annealign using Annie and Templilaq (see below) I got cooked carbon and hard seating without a lube (first round, next are fine)

So another aspect of this is should the case be cleaned with Steel Pins and solution to get perfectly clean (I think its a good idea but equipment cost has me short of that yet)

Supriecub 99 also came up with the perfect answer to the wet cases, cheap food dryer from Wallmart works perfectly.

Then there is my experience with my testing method of Templiaq (which is the same as torches use)

https://thefiringline.com/forums/showthread.php?t=588267

In short this is not ever going to be perfect, it takes serious attention and AMP if it does off you will not know it until you shoot the brass.

I am for under annealing deliberately as not to go over and I am not after perfect.

There is good enough (a tad under) and then there is the iffy statement of perfect with so many variables and no feedback mechanism to see that.

[JASmith]

I full length size after annealing.

This puts some work hardening back into the brass. I think the step also makes the yield strength more consistent because strain hardening is fastest at the beginning and tapers off. That means that the spread of yield strengths is reduced.

The strain hardening curve might also explain why some folks report better accuracy with cases that have been fired one or more times. I report "some" folks because my shooting skills aren't in their ballpark! :rolleyes:

[Blitzfike]

The additional carbon inside a dirty case provides a material that reacts to the electromagnetic field of the induction coil. More carbon to get hot from being in the induction field, more heat to the brass case.