Why not use expander balls?

[woods]

My mandrels take this up and springback leaves ~1.5thou under cal. Given enough reloading these creep up to near ~1thou under cal.

With continued reloading the hardening increases and springback increases, no?

So with the mandrel springback coming back in, wouldn't this increase the bullet grip over time and it creep up to 2 thou under cal?

 

[Mikecr]

Woods I'm not downsizing enough to cause that. If I sized down 3-4thou under, and then expanded, greater springback would lead to ever tightening bullet grip as you describe.

And don't forget that increased springback also counters downsizing. So over time my downsizing springs back to ~2thou under instead of 2.5thou under.
This is over many reload cycles though.

 

[woods]

Yeah so the inward/outward sizing offset each other

Hate to hijack this thread but I am interested in your outside neck turning or inside reaming to get case neck thickness consistent enough to be so finite in your measurements and processes

What tool do you use?

 

[Mikecr]

I neck turn with Sinclair's NT series(4000 now), and a Neil Jones case lathe.
I measure thickness with Sinclair's IP54 ball mic.

 

[TracySes23]

[/QUOTE]Another subject, but:
To have control over actual bullet tension you need to have control over springback, which means you need springback. Annealing can greatly reduce springback, and this can remove control over it.

Annealing does 3 things: It increases seating forces AND reduces bullet tension AND affects your control over it otherwise.
With this, your tension and consistency of it comes down to the precision in your annealing. So if you're going to do it frequently, I recommend you invest in the best available process for it.[/QUOTE]

I'm at a loss as to how annealing can cause an increase in seating forces, unless it somehow increases the coefficient of friction, though the burning off of the carbon you suggest is a good lubricant. Please help me understand this.

Spencer

 

[Mikecr]

I'm at a loss as to how annealing can cause an increase in seating forces

It's because annealed necks are left smaller with a given amount of sizing(same sizing as non-annealed). With this, a seating bullet has to upsize the neck more.
The extra seating force from annealing makes people think annealing restores tension, but reality is just the opposite.
This is context based on downsizing, with no pre-expansion prior to seating bullets.

 

[woods]

It's because annealed necks are left smaller with a given amount of sizing(same sizing as non-annealed). With this, a seating bullet has to upsize the neck more.
The extra seating force from annealing makes people think annealing restores tension, but reality is just the opposite.
This is context based on downsizing, with no pre-expansion prior to seating bullets.

But with an expander ball the seating force would be decreased because the expander expands the neck brass outward, and with less springback due to annealing, the brass would spring back less inward

With a bushing die sans expander or a Lee Collet there would be more seating force due to the sizing operation sizing the brass inward and then less springback outward leading to a smaller ID

Correct?

 

[Mikecr]

Yes, that's correct

 

[Jcub]

This thread was full of some high level stuff.lightbulb

 

[Canadian Bushman]

This thread was full of some high level stuff.lightbulb

A lot more than i was expecting. If anything it talked me into using expanding ball/mandrels

 

[cdherman]

But with an expander ball the seating force would be decreased because the expander expands the neck brass outward, and with less springback due to annealing, the brass would spring back less inward

With a bushing die sans expander or a Lee Collet there would be more seating force due to the sizing operation sizing the brass inward and then less springback outward leading to a smaller ID

Correct?

Well, I don't know the answer, but I agree with your logic. I agree that this thread is great food for thought.

I have stayed with my ball expander. I leave it loose, and out of my forster co-ax press, it certainly should not disrupt the symmetry of the case while sizing. (the co-ax allows the dies to move some as well).

But I am considering annealing. I've neck turned in the past, but never saw an improvement.

I am contemplating this sequence as a possible theoretical "nirvana":

1) Resize after firing with a body only die, taking about 2 thousands back off the shoulder. Leave the neck in fired state.

2) Use an inside neck reamer, custom cut to reflect the guns chamber neck, minus about .028 (2x .0014). This should knock out any donut or bad thick spots.

3) Anneal. The expensive units are good I suppose, but Tempilaq 750 and a pair of opposed torches and a "spinner" on a drill where I can drop the case out of the flame the instant the tempilaq melts should work.

4) Collet resize, versus bushing resize, based on what you can get. Would aim to use bushing to go about .004" less than bullet. Springback after annealing should be minimal.

5) If you can get it, run a mandrel through the case at the end, about .003" less than the desired bullet diameter.

The annealing stage of this sequence would mean that the latter stages of collet/bushing sizing are minimally affected by springback, as would be the mandrel. There are threads about several shooters who now anneal after ever shooting.

The mandrel and annealing should result in a very consistent neck tension and no donut effect.

I don't know -- for the casual reader, please don't assume that my idea above is gospel. Never tested. Just throwing it out for comments.....

 

[rooster721]

I personally have stuck (so far) with full length dies bumping 2-3 thou in my rifles.. and also still use my expanders. I am considering a switch to neck/bushing dies but have many overhanging questions and concerns.. one major-one being, that I was always under the impression neck-turning is basically mandatory in-cahoots with bushing neck-sizer dies in order to see real benefit from them (and not off-set un-even necks off centre making matters worse-yet, if you don't turn them the same time to uniform*) I (also) always understood that neck turning itself is frowned upon in bigger hotter calibres (like RUMs and other big magnums that a LR hunter might shoot) because of that brass' tendency to have a shortened life-span as it is, due to neck splits, nevermind yet take more away by turning* (so i-dunno ??) What's the real answer. Seems like a damned if you do, damned if you don't thing. Maybe supposed to find a happy-medium (with the bigger hot cartridges) and stay quiet ?

I myself have gone the route of annealing now and am using my same old FL dies with expander balls, to avoid an even-worse connundrum like I mentioned possible above. I ran a batch of brass last night in fact and can "feel" a world of difference levering cases in and out of my dies compared to no annealing. More case-to-case consistency through my sizer for sure. I can't say anything about seating or groups or really much else as of yet, but am hoping that my adjusted routine to:
-de-prime
-clean
-(now) anneal
-FL size
-trim (however needed/if so)
-primer-pocket uniform & then,
-flashhole de burr... (if brass never done) ...will solve "some" of my-own grouping/load discrepencies and differences

My rifles are all bigger heavier magnums ALL used as hunting rifles as well as target, so gotta work reliably "all around" Unless I have understood wrong all along, my cartiges may be in the category that this annealing route may be better..?.. THAT I guess will remain to be seen. Bottom line, I think all reloading tools, routines and methods have their place... and all cartridges in-themselves fall into different categories as to where each method/tool/routine is best suited to application

Correct me if I'm wrong.. but this is the conclusion I've come to so far

 

[Canadian Bushman]

Rooster,
Your logic is sound and correct but id like to add a few things. Neck sizing only can make cases hard to chamber but thats dependand a lot on the case dimensions as well as a few things the hand loader does. I personally have some cases ive neck sized six times and still chamber fine. This preserves brass quite a bit. Also saves you some trimming.

Neck bushings, ns dies and fl dies will all push deviations in thickness to the inside. Why i like expanding the case from the inside, to push it back out.

Neck bushings do work much better with cases that are neck turned, but your other dies will as well. Neck bushings basically allow to tune how much you are working the neck.

If you neck turn a case too thin you will have boat loads of problems mainly because the case is expanding and contracting what it already was plus what you took off by neck turning. By only turning off enough to clean up diff in thickness you can minimize this problem. On average i turn off .0005-.003 inch to get my cases to clean up. In turn i work the brass about .005 - .007 less by using a busing die to size it back down after firing.

As often as you anneal i doubt you will split necks and you will add some more consistancy to your handloading. I didnt notice much improvement in accuracy but did greatly improve my brass life and reloading consistancy by adding neck turning and neck sizing to my routine. Neck sizing will annoy you and add time to intial brass prep, thankfully you only have to do it once.

Just offering my thought hope you find this helpfull. Happy hunting

 

[DocB]

A couple of questions:

Mike: do you turn the full neck then partial neck size on 1/8" for tension?

Kennibear: If I understand you correctly, you decap and expand at the same time then later neck size with the Lee Collet sizer?

Thanks,

DocB