Has your neck splitting issues been resolved?

after the first firing from the annealed case batch, none so far. I'll resize them and see. The recrimped cases didn't affect velocity

Thanks for updating. I was looking into annealing for more consistent neck tension more than case life. I get about 5 cases out of 100 that'll seat lighter (by feel) than the others. I use those as practice or sighters. I'll usually lose my primer pockets before cracking necks.

How about the salt bath annealing method? Seems simple enough, relative inexpensive and controllable as far as temps are concerned. The only problem I see is letting the salts get hot after dipping a few rounds.

** double post **

I just read about that as well. Seems more precise than a flame.

How about the salt bath annealing method? Seems simple enough, relative inexpensive and controllable as far as temps are concerned. The only problem I see is letting the salts get hot after dipping a few rounds.

Really interesting method.  The salt has a huge heat capacity but should not be overheated.  From his website
" If heated above 590°C this salt will begin to decompose, releasing hazardous nitrogen oxide fumes .  At higher temperatures the salt becomes a powerful oxidizer that may cause spontaneous and violent ignition of flammable materials including wood, wax, oil, plastics, and light metals.  Use only in a well ventilated area.  If at any point in your annealing session the pot begins to make a sound like a boiling kettle, emits visible fumes, or the salt begins to develop a yellow colour you are running the pot too hot.  I do not recommend using this salt without a temperature measurement device that is known to be accurate in the range of 300°-600°C."

Needless to say, like anything else proper precations need to be taken to prevent fire or severe burns.

interesting. I need some time to understand the findings
https://www.ampannealing.com/articles/40/annealing-under-the-microscope/

and another experiment
https://www.ar15.com/forums/armory/Brass-Annealing-Experiment-does-it-improve-muzzle-velocity-variation-/42-484392/

interesting. I need some time to understand the findings
https://www.ampannealing.com/articles/40/annealing-under-the-microscope/

and another experiment
https://www.ar15.com/forums/armory/Brass-Annealing-Experiment-does-it-improve-muzzle-velocity-variation-/42-484392/

That first link is gold.  Thanks for sharing! 

My thoughts on annealing
I did some annealing on my 6mmBR brass. I did it by hand with a torch. Lapua brass that had been fired ten times. The rifle shot .2 inch groups before and after annealing. the only thing I noticed was less spring back from sizing. The only reason to do it, in my opinion, is to prolong the life of your brass. If you are using expensive brass, it could be worth it. Eventually primer pockets get loose and you gotta throw it out anyway. If you're loading hot rounds the primer pockets go quick. I wouldn't waste my time annealing for a semi-auto rifle, they tend to beat up brass and it's usually cheap anyway.

Annealing can be done very accurately by hand with a torch. You have absolute control and you are looking at every case. It's cheap too. All you need is a torch and a pan of water. Some tempalac till you get a feel for it. I would recommend a glove too. You can do 2 or 3 without, then the finger tips start to get hot. the longer the cast the easier it is to anneal.

after the first firing from the annealed case batch, none so far. I'll resize them and see. The recrimped cases didn't affect velocity

Do you resize your necks? The article on amp annealing mentioned the following regarding hardness:

So how quickly do case necks work-harden with reloading? The answer is: really quickly. Just one pass through a standard resizing die with an expander ball is usually enough to add 20 HV + to the hardness. Seating the bullet adds another 5 – 10 HV. Interestingly the actual shooting of the cartridge has a relatively minor effect. We also found little difference between regular and "hot” loads, but this is just in relation to neck hardness. "Hot” loads are harder on brass for other reasons.

The reason your necks may be splitting is they are becoming hard to the point of becoming brittle... so that when fired they split rather than expand and seal against the barrel throat.

Like I said this info you sent was gold... and I am eager to see whether the annealing resolves the issue.  If so the next question is what is the optimal hardness for the annealed neck?

My thoughts on annealing
I did some annealing on my 6mmBR brass. I did it by hand with a torch. Lapua brass that had been fired ten times. The rifle shot .2 inch groups before and after annealing. the only thing I noticed was less spring back from sizing. The only reason to do it, in my opinion, is to prolong the life of your brass. If you are using expensive brass, it could be worth it. Eventually primer pockets get loose and you gotta throw it out anyway. If you're loading hot rounds the primer pockets go quick. I wouldn't waste my time annealing for a semi-auto rifle, they tend to beat up brass and it's usually cheap anyway.

Annealing can be done very accurately by hand with a torch. You have absolute control and you are looking at every case. It's cheap too. All you need is a torch and a pan of water. Some tempalac till you get a feel for it. I would recommend a glove too. You can do 2 or 3 without, then the finger tips start to get hot. the longer the cast the easier it is to anneal.

Per the article Ren referenced annealing make the neck softer which would be consistent with your observation that the brass had less spring back.  Were you using propane on your torch?

I full size resize with a Lee die.

Per the article Ren referenced annealing make the neck softer which would be consistent with your observation that the brass had less spring back.  Were you using propane on your torch?

I used map gas. It's hotter so it heats up the neck/shoulder before the heat spreads down the case. That's the idea anyway.

Good discussion so far. I've heard of many precision shooters that anneal every firing not so much for extended case life but for consistent neck tension. Some of them feel neck tension and seating depth is more important than powder charge.

Good discussion so far. I've heard of many precision shooters that anneal every firing not so much for extended case life but for consistent neck tension. Some of them feel neck tension and seating depth is more important than powder charge.

Bullets don't lie, as they say.  Annealing is at it's heart softening the brass or put another way, reducing the hardening effect that the neck sizing die has on the case.  It will be interesting to compile a catalog of optimal annealing and seating depth for different loads.  The question is how to actually measure the amount of hardness removed by the annealing process at the reloader level.

I anneal after every firing right after wet tumble. I do it to prolong my brass. The only thing I notice was there was less bullet runoff or no runoff at all after seating. I checked 5 bullet seated on annealed brass and 5 with non annealed brass. The non ones I had runoffs of 4-5 thousands runoff. The annealed ones was hardly to 2 thousands off. But don’t take my word for it, maybe it has a lot to do with type of dies and conditions and process of brass, bullets used and prepping. I’m not going for precision type of ammo. But, just do it to see how much of the prepping I did came out. I use a AMP annealer and the Hornady concentricity tool. Just my 2 cents.. 

I anneal after every firing right after wet tumble. I do it to prolong my brass. The only thing I notice was there was less bullet runoff or no runoff at all after seating. I checked 5 bullet seated on annealed brass and 5 with non annealed brass. The non ones I had runoffs of 4-5 thousands runoff. The annealed ones was hardly to 2 thousands off. But don’t take my word for it, maybe it has a lot to do with type of dies and conditions and process of brass, bullets used and prepping. I’m not going for precision type of ammo. But, just do it to see how much of the prepping I did came out. I use a AMP annealer and the Hornady concentricity tool. Just my 2 cents.. 

Interesting and thanks for sharing. What kind of seating die and press are you using if you don't mind me asking?

I anneal after every firing right after wet tumble. I do it to prolong my brass. The only thing I notice was there was less bullet runoff or no runoff at all after seating. I checked 5 bullet seated on annealed brass and 5 with non annealed brass. The non ones I had runoffs of 4-5 thousands runoff. The annealed ones was hardly to 2 thousands off. But don’t take my word for it, maybe it has a lot to do with type of dies and conditions and process of brass, bullets used and prepping. I’m not going for precision type of ammo. But, just do it to see how much of the prepping I did came out. I use a AMP annealer and the Hornady concentricity tool. Just my 2 cents.. 

Hit the nail on the head!  Brass life is greatly improved with annealing.  Chasing around neck tension from only annealing doesn't make a whole lot of sense, when neck thickness of many brass can be out over .010 in some cases...

 Accuracy with brass annealing doesn't come from neck tension, it comes from sizing/headspace consistency. With the neck and shoulder annealed, the brass is more consistently sized/headspaced, this, in turn, makes more consistent ammo. 

If you want OCD neck tension, then the best way to go about that, is to either turn necks or sort them per neck thickness.

I tried both, and settled on sorting them to within .002" variance per side.  That, IMO, is good enough for the max ranges I can shoot here. (600yrds)

Interesting and thanks for sharing. What kind of seating die and press are you using if you don't mind me asking?

Redding type S FL bushing die (without expander ball), Forster micrometer seater die,, and RBCS Rock Chucker.