Annealing Issue

[eshorebwhntr]

Been annealing for about 10yrs now. Had a new issue today that I've not experienced before.

3x fired WW 7mm Mag brass. Had a neck start to split. Annealed them with a flame, approx 7 sec.

Resized with a FL die after annealing.

Just seated a bullet to my COAL and when I checked it with my calipers I pushed the bullet all the way in the case.

I've got ways to get around it I'm just wondering if anyone else has experienced this.

 

[Hunt_4life]

What kind of fl die? Seem like simply the wrong neck tension. Can you change the bushing? Or can you pull the expander out and use a expanding mandrel? Did this happen with more than one piece of brass?

 

[PddPdd]

What die are you using for full length resizing? If it's a bushing die, was the bushing in? What is the neck ID after sizing (if you have a way to measure it)?

 

[Tac-O]

I have done it. The brass was overannealed when it happened to me. I was using a 0.306 expander for a 308 bullet, so there should have plenty of neck tension but the brass neck was just too soft.

 

[Pdyson]

I over-annealed one once and the neck crushed and another buckled in seating. Any chance you got a 270 bullet mixed in? With .003 or 004 neck tension a 7mm case might lightly hold one.

 

[Petey308]

I started annealing several years ago now, using a drill, socket, and torch. It appeared to work and give better results than not annealing- or so I thought. Then the shooting sport became more and more popular, technology advanced, and we started getting better tools to actually see results more than just on target. Chronographs got much better and more precise. We even have reloading presses with load cells that can accurately measure pressure/force required to seat a bullet. So now we know annealing does make difference for sure, but it really needs to be done properly to actually produce consistent and proper results. It needs to be controlled and very consistent. A torch and a drill leaves far too many inconsistencies and the results are typically not proper and almost never consistent. You'd be better off not annealing and just buying fresh brass. I only anneal by induction now.

Sure, some guys are getting by still just fine for their needs with a torch and drill, other flame annealing methods, and even salt bath annealing, but I'd go out on a limb and say most of them aren't shooting for top precision and don't really care about getting top consistency from it. Nothing wrong with that since we all have different needs and goals. I would say though that improving your annealing method would likely help you in your situation. Or just buying new brass when it starts splitting.

I'll assume it's not your die setup since it sized the brass fine the previous firings up until this one. It sounds like you got the brass too soft, but hard to say for certain.

 

[dfanonymous]

Yes the 7 seconds of flame time doesn't really matter. I turn of the lights and set up the annealer to right about when the case starts to glow. It's annealed at that point. The time it takes to get there vary per manufactures of brass sometimes from my experience.

 

[eshorebwhntr]

Lee FL die with factory expander. Done this many times in the past with various other cartridges. Not sure why this happened this time.

I checked several pieces. All the same. Brand new box of 7mm bullets.

I'm going to see if removing the expander and sizing the neck down will improve it. Don't have bushing dies to play with for this cartridge.

I'm curious about the over annealing. I've watched and read a ton on annealing in the past several years. I for one have never felt the need to anneal for the sake of maintaining accuracy or precision, only keeping good brass from splitting or cracking and the flame method has worked well for me until today.

I'm sure based on what I've researched that the AMP system is a quality piece of equipment, I just can't justify the cost for my needs.

Erik Cortina has a few videos on this that I've watched that I think are very well done. In one case a metallurgist watched and responded to his videos. They're worth watching IMO.

Thanks for the responses. I'll keep updating if I find anything significant.

 

[eshorebwhntr]

Yes the 7 seconds of flame time doesn't really matter. I turn of the lights and set up the annealer to right about when the case starts to glow. It's annealed at that point. The time it takes to get there vary per manufactures of brass sometimes from my experience.

Generally how I do it as well. 6-7s is how I got there for this lot.

 

[Tac-O]

Generally how I do it as well. 6-7s is how I got there for this lot.

Maybe try a few more keeping everything the same but doing 0.5-1s shorter on anneal time and see if you have the same problem.

Were you able to move the bullet after seating on all of them? Or just a couple?

 

[eshorebwhntr]

All of them

 

[Hunt_4life]

Just thought I'd ask but did you anneal before or after resizing because annealing after resizing could affect your neck tension and make your case grow.

 

[eshorebwhntr]

Annealed then sized

 

[Reelamin]

A one off does not make it a problem for me. I would say it was just a bad piece of brass. You could go anneal extreme another piece of the same bunch (try it) and it wont split is my bet.