time to anneal?

ffwd

ffwd

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I'm on my 5th loading with my (Norma) 7mm Weatherby brass. Trimmed on the 4th. The first few cartridges I seated bullets in, did not have sufficient neck tension to hold the bullets seated. I removed the expander ball from my neck sizing die and ran all the cases through it to increase the neck tension. All bullets are seated firmly now. I'm thinking I should anneal the necks on the next go round. Yes?
 
Done properly, annealing can't hurt and may uniform your muzzle velocity as work hardened necks result in increased but less uniform velocity. In the meantime measure your expander ball. If it is on the large side of the spec you may want to polish it to slightly reduce it's diameter and allow it will also pass through the neck with less resistance.
 
I was going to make the expander ball small enough to pass through the neck without touching at all. Increased neck tension for all! I wanted to try it anyway. I've read a few different methods to anneal and haven't decided which one I would go with yet.

Torch in a dark room heat up to dull red (I think) drop in a bucket of water.
Cases stood up in a pan with enough water to cover the case head, heat up in over and knock cases over into water.
Tempilaq (can't remember which temp rating. info on 6mmbr.com) inside case mouth, heat with torch til it melts, let air cool
Build a machine that spins the case neck through a flame for a specific amount of time and allows case to cool in air.(info on 6mmbr.com)
 
The system is use is to hold the case near it's base and rotate the shoulder in the flame with the neck pointed upwards. I don't worry too much about the color, when I have to drop the case into the water, my pain threshold produces pretty uniform results.
 
Low case neck tension could well be caused by being well up the yield curve, resulting in lots of spring back, so trying annealing isn't a bad idea.

I think the simplest annealing method is similar to Boomer's. But, you need to do a couple by colour change to get a feel for timing. Relying on heat to the fingers will mean short cases don't get hot enough while long ones get too hot. Best is to take one case and twirl it in the flame to a count of three steamboats, then drop onto a damp towel. Wait until it cools then look at it. You want a visible colour change to the neck and shoulder after the case is cool. If the case starts to glow, drop to 2.5 steamboats, if no colours show up move to 3.5 steamboats and repeat. Once you get the feel of it, do the cases by counting steamboats. When you are done, you should be able to lay them all out side by side and they should all look very similar. Remember that if you change the flame height at any point it will affect your timing.

The torch and pan method is messy, slow and most people badly overheat their cases. There is no need to drop into water with any of them, you won't have to let them dry if you use a damp towel.

And while I like the article on annealing on 6mmBR.com. I don't believe the temperatures they post there have any credibility. They are just pulling them out of the air. I am not aware of anyone doing any real study to find the proper temperature for home annealing.
 
While you could anneal, I believe that your experience has nothing to do with the properties of the brass. You mentioned that you trimmed the cases and then noticed that the bullets didn't seem to seat with the same tension. I suspect that your trimmer used a mandrel, and that when you trimmed this mandrel expanded and smoothed the inside of the neck.
 
I trimmed before the 4th go round. I think if I noticed the decreased neck tension then, I would have run the cases through the way I did this time......and I probably would've started this thread a few months ago. Is it even possible to show up 1 firing later?
 
ffwd said:
I trimmed before the 4th go round. I think if I noticed the decreased neck tension then, I would have run the cases through the way I did this time......and I probably would've started this thread a few months ago. Is it even possible to show up 1 firing later?
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I have heard that if you wish to have your brass last, you should anneal after the 3rd or 4th firing. Some fellows do it after each firing. FS
 
I have read that as well. I wanted to have hard data regarding when I needed to do it. So I guess I need to go fire these loaded rounds and hope I don't split any necks.
 
If you do decide to anneal, you can use a wooden skewer (cheap, found everywhere) to hold a case by the primer hole. I saves you fingers, and you can easily spin it doing the neck evenly.

I have also found that annealing in a basement room in really low light helped. I could easily see when the metal got hot enough.

Som eguys anneal in lead. If you cast bullets you can try that too.
 
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