When do cases need annealing

[gpointer]

very well put I would like to see the groups Mikb gets with his 20 times fired brass

[Jehoolio]

As stated way back, only neck sized my cases and into high teens reloaded. Still getting sub 1/2 minute groups out 1000yds.
I think this annealing craze is a load of ballcocks.
Might well help with those people who practice bench rest.

I'll stick to neck sizing I think.

[bewsh]

As stated way back, only neck sized my cases and into high teens reloaded. Still getting sub 1/2 minute groups out 1000yds.
I think this annealing craze is a load of ballcocks.
Might well help with those people who practice bench rest.

I'll stick to neck sizing I think.

totally agree, neck sizing with a collet or bushing die is "one way sizing"
couple that with moderate loads in soft brass and in an accurate rifle and you may never need to anneal

I have 8, 9, 10x fired Norma brass in .270 shooting 130gr over 55gr of N160 - very moderate load
I also have similarly high firing .222 norma brass from 60gr over 20.8gr N133 - also moderate
I collet neck size
no drama

step that up to a hot load and numerous FL sizing and its not a case of "if" its a "when"

2-3x firing of Lapua (hard) brass in .243 (getting towards an overbore situation) shooting 47gr N160 under 87gr Interlocks as the necks were so hard the soot reached the case head (lack of case obturation in the chamber due to work hardening)

£10 on annealing and they were just like the first time

[Jackel]

Ah, Ackers - bless, I miss him .

We don't

[Randy Bohannon]

I confess I agree that consistent metal properties are the key to consistent mechanical properties.

If you use a Lee collet die for example the degree of spring back is a function of brass hardness and therefore neck tension decreases as the case work hardens but this happens very slowly.


Fl sizing can be a tricky one as because it undersizes and then expands the work hardening can average out or go some other way.


Annealing is something that a lot of the pure precision boys do unless they have chambers so tight that the neck is barely worked in the firing and reloading cycle anyway.

[David TS]

Ah, Ackers - bless, I miss him .

We don't

I know you don't mean that Carl .

[Jackel]

I know you don't mean that Carl .

I was the banning Mod and glad to say that

[angrybear]

Being what I believe is classed as a "wildcat" case & only having a full length sizer, I guess I'll be doing some then

[MikB]

you are double sizing with a FL die (squeeze and stretch)

your half grain off book max demonstrates nothing, the book max is for the rifle they used with the component for that data

quite possible to run high pressures in your rifle with significantly less than book max...its a guide

Name a process that uses work hardening in a metal component that requires it to be malleable and not brittle
"Work hardening" is done through work not a defined action or process, all metal hardening is done to alter the crystal structure and make the metal less malleable.
You can not get reliable neck tension using work hardened brass, you have work hardening each and every neck differently with different loads and pressures in FL sizing

Annealing is the CONSTANT not the variation (assuming same alloy component mix and dimensions the spring rate of the metal will be uniform)

crack on with your rock hard, work hardened brass if it works for you but your comment of consistent pressure when seating doesn't indicate your brass is consistent or your neck tension is good

when you size a case you under size it
when you seat a bullet you are forcing an object into a hole usually 0.002" smaller
the neck tension comes from the elasticity of the brass alloy as it resists the over sizing action of the bullet.

you simply can not get consistent neck tension (which above all other things is fundamental to the production of repeatable pressure curves, which in turn is one of the key elements of the bullet leaving the barrel on exactly the same point of the barrel oscillation to produce repeatable POIs) from work hardened brass

the brass doesn't spring back and resist the oversizing action of the bullet being seated

but hey, what do I know
people must do it for a laugh........

Well, I hardly know where to start, but let's begin by saying there's no point in trying to name a workhardening process that requires the metal to be malleable and not brittle because you're making a bogus dichotomy out of two ends of a spectrum. Annealing doesn't just remove brittleness, it takes out the elasticity too. That's why old bikers used to anneal copper headgaskets (well, I used to, anyway), so they'd take the texture of the mating components without springback and provide a good seal. You wanted the gasket to be malleable, but you want a case neck to be springy enough to provide tension when you seat the bullet with a couple of thou interference, not just open up like boiled macaroni.

So you're quite right in wanting consistent neck tension, but I didn't find I got much at all, consistent or otherwise, from soggy brass.

I've never been a top target shot, but I could do a 72 out of 75 with a good number of Vs at 600 in a tricky wind, on a good day - and I'm pretty sure any faults had more to do with my aim than my ammo.

The simpler the process, the lower the risk of unanticipated variables.

Regards,
MikB

[bewsh]

Annealing doesn't just remove brittleness, it takes out the elasticity too. That's why old bikers used to anneal copper headgaskets (well, I used to, anyway), so they'd take the texture of the mating components without springback and provide a good seal.

You wanted the gasket to be malleable, but you want a case neck to be springy enough to provide tension when you seat the bullet with a couple of thou interference, not just open up like boiled macaroni.

Actually it doesn't
"Elasticity" is far greater in ductile metals, Annealing improves ductility - that's just a fact

nice analogy of boiled macaroni but it doesn't quite work like that.
the harder the alloy the less "springback" or "elasticity"
it just opens and stays open when you force the bullet in

not suggesting you can't shoot as a result of not annealing, clearly the scores you post are above average

but...physics is physics.
Its not really open to debate...

examples galore if you look

http://paperity.org/p/16721797/effec...anocrystalline

2. The variations in the hardness and modulus of elasticity
of (ED) nc-Ni with annealing temperature
define the following three regions.
a. Region I at 300 K (27 C) <T<350 K (77 C): in
this region, the hardness and modulus of elasticity
of the nc-Ni remain essentially constant.
b. Region II at 350 K (77 C) <T<500 K (227 C):
in this region, the hardness and modulus of elasticity
of nc-Ni increase with increasing grain size and
the holding time has no significant effect on the
value of the hardness.
c. Region III at T>500 K (227 C): in this region,
the hardness drops and then decreases with
increasing grain size. In addition, in this region, the
hardness depends on the holding time: the higher
the holding time, the lower the hardness. On the
other hand, the modulus of elasticity approaches a
maximum value of ~240 GPa.


http://ccsenet.org/journal/index.php...load/8443/6280

"cold-drawing deformation and subsequent annealing have a great influence on
the super-elasticity."


SUMMARY = the lower the hardness - the higher the elasticity

but we seem to have strayed into a darker area than perhaps the OP wanted to.....

[gpointer]

Actually it doesn't
"Elasticity" is far greater in ductile metals, Annealing improves ductility - that's just a fact

nice analogy of boiled macaroni but it doesn't quite work like that.
the harder the alloy the less "springback" or "elasticity"
it just opens and stays open when you force the bullet in

not suggesting you can't shoot as a result of not annealing, clearly the scores you post are above average

but...physics is physics.
Its not really open to debate...

examples galore if you look

http://paperity.org/p/16721797/effec...anocrystalline

2. The variations in the hardness and modulus of elasticity
of (ED) nc-Ni with annealing temperature
define the following three regions.
a. Region I at 300 K (27 C) <T<350 K (77 C): in
this region, the hardness and modulus of elasticity
of the nc-Ni remain essentially constant.
b. Region II at 350 K (77 C) <T<500 K (227 C):
in this region, the hardness and modulus of elasticity
of nc-Ni increase with increasing grain size and
the holding time has no significant effect on the
value of the hardness.
c. Region III at T>500 K (227 C): in this region,
the hardness drops and then decreases with
increasing grain size. In addition, in this region, the
hardness depends on the holding time: the higher
the holding time, the lower the hardness. On the
other hand, the modulus of elasticity approaches a
maximum value of ~240 GPa.


http://ccsenet.org/journal/index.php...load/8443/6280

"cold-drawing deformation and subsequent annealing have a great influence on
the super-elasticity."


SUMMARY = the lower the hardness - the higher the elasticity

but we seem to have strayed into a darker area than perhaps the OP wanted to.....

your wasting your time and effort as you cant educate a man who wont accept the facts,hes obviously top class target shooter whos that good should be in the England team with those scores from brass fired 20 times,may be he should tell the world record holders there wasting there time annealing LOL

[dannywayoflife]

Why would lapua anneal if it was pointless?

[MikB]

Why would lapua anneal if it was pointless?

Because they're making the cases, and that's a process several orders of magnitude more severe than reloading them.

Regards,
MikB

[dannywayoflife]

Personally I'll continue to regularly anneal it works for me

[MikB]

2. The variations in the hardness and modulus of elasticity
of (ED) nc-Ni with annealing temperature
define the following three regions.
a. Region I at 300 K (27 C) <T<350 K (77 C): in
this region, the hardness and modulus of elasticity
of the nc-Ni remain essentially constant.
b. Region II at 350 K (77 C) <T<500 K (227 C):
in this region, the hardness and modulus of elasticity
of nc-Ni increase with increasing grain size and
the holding time has no significant effect on the
value of the hardness.
c. Region III at T>500 K (227 C): in this region,
the hardness drops and then decreases with
increasing grain size. In addition, in this region, the
hardness depends on the holding time: the higher
the holding time, the lower the hardness. On the
other hand, the modulus of elasticity approaches a
maximum value of ~240 GPa.

Whatever the condition that's supposed to be describing, it doesn't match my experience.