Home Forums Reloading Big Game Rifles Redding Neck Die

I have a 'Deluxe Set' with the FL,NK, and seater dies.

I have the FL die set up and can get .001-.003 runout after resizing.

I cannot get the NK die to do anything less than .008 - .010

I have adjusted the die up and down, adjusted the stem up and down in the die, even tried a rubber washer between the die and press. It will not do any better.

What am I missing?

-Dustin

Conventional neck size dies don't support and align the case the way a good FL die will, and they generally don't produce runout numbers as good.

If you want to neck size and get straight brass, then you want a Lee collet die or a bushing type die that sizes the brass just enough.

I should say your particular neck die may have a problem, but my earlier statement holds for conventional neck dies in general.

I would agree.

Have usually had better luck partial-sizing with FL dies than using neck-sizing dies. The exception is cartridges with very parallel sidewalls, where the neck die sometimes (not always) is close enough to case diameter to support the brass while the neck's being pulled over the expander ball.

Remove the expander and spindle assembly from your neck die, size the neck and check your runout. If the runout is reduced your expander and spindle assembly are the cause of your runout.

The question isn't whether the expander ball is the cause of the run-out. In conventional sizing dies it almost always is, or has been since RCBS quit reaming necks separately in their sizing dies, quite a few years ago.

I have yet to encounter a Redding sizing die where the neck was out of alignment with the body.

If the expander and spindle assemble are locked down off center or slightly bent the case neck will be pulled off center as it is pulled over the expander. And the biggest cause of neck runout is caused by the expander than any other reason followed by uneven neck thickness.

The Forster bench rest dies have the high mounted expander that prevents this. The Forster expander floats and enters the case neck when the neck is still centered in the die. The rubber washer (W-10) below allows the expander spindle to move and self center in the case neck.



The Forster expander works so well I installed them on all my RCBS sizing dies. The converted .223 die below is producing cases with .001 or less runout after sizing,



And the reason I stated to remove the expander and then check neck runout was to see if the expander was the cause of the runout.

And I'm saying that testing isn't required to determine if the expander ball is the problem, because it always is--unless as noted the sizing die is old RCBS (or possibly some other brand) where the neck and body of the sizing chamber are out of line with each other.

I haven't bothered testing any new dies for this for many years, because the necks of the sizing chamber haven't been out-of-line, with any brand, including RCBS.

As for the Forster assembly, I do essentially the same thing, at far less expense, with RCBS dies (and some other brands) by raising the expander ball assembly to just under the neck section of the die. Once I know how high that is, I place rubber grommets of the right diameter on the spindle, above the top of the die. The grommets hold the spindle in the correct position, and allow the loosened spindle to self-center in the neck of the case. This costs less than a buck. I always have a Lee decapping die in one hole of my Redding T7 anyway, so decapping isn't a problem.

The expander isn't always the problem, if the case has unequal case wall thickness the case can warp when fired and become banana shaped.



And by raising the expander you are not doing the same as the Forster expander. Below on the left is a RCBS expander assembly and on the right is the Forster unit. With the Forster expander assembly the expander is much higher and the case neck is "fully" supported and centered in the die as the expander enters the case neck. Meaning the expander is always centered in the case neck and the RCBS expander is not, and because of this the "lower" mounted expander can induce neck runout. Meaning you will "never" get the RCBS expander as high as the Forster unit and have the case neck supported by the die.



Also rifles like the AR15 can chew up your rim and extractor groove. And any ding inside of the rim can cause the case to tilt on the down stroke of the ram. With the Forster unit the neck can not tilt on the down stroke of the ram. I used the "cheaper" method you described and it did not reduce the neck runout as much as the Forster unit does.

So one more time, you check the case after sizing "without" the expander to eliminate the expander and also check to see if the case is warped from firing. And you can't eliminate the neck runout possible causes without removing the expander.

So do the OP a favor and stop telling him he doesn't need to remove his expander to eliminate what could be inducing his neck runout.

Even if the neck thickness is uneven, a neck-sizing die isn't going to turn a case banana-shaped, and neither is firing the case, unless the chamber of the rifle is wonky. Only a full-length die will do that. Or at least that's been my experience in measuring a bunch of cases with lop-sided necks.

In RCBS dies, you can raise the expander ball just as high as it is in Forster die. In fact you can raise it so high in many RCBS dies the neck of the case won't even go into the neck portion of the die. I have tested this technique a bunch of times, alongside Forster dies.

Redding neck expander buttons are the size of bull pricks. Why on earth would anyone engineer such a massive cylinder to yank back thru the necks?

Use a Lee Collet die if it's available in your cartridge and never look back . . . .

Redding dies get an immediate swap to a carbide ball or one of their tapered expanders.

You should see the expander, truck axle, drill stem, whatever that came out of an old Lee 308 Win. FL die I have.

Lee's current tapered expander is really good.

If the case has unequal wall thickness the thin side of the case will expand more than the thicker side. These cases will warp and become banana shaped when fired.

I posted photos of the NECO gauge which clearly states this and the RCBS expanders and you still want to argue with photographic proof. In my photo the RCBS spindle is raised as high as it will go and the Forster expander is in its normal position.

It is obvious you do not have the gauges to measure this warping of the case when fired and your lack of knowledge and experience is showing.

I just went out and measured it. The bearing surface is 1.25" long.

mmm How about using an "O" ring, leaving the stem to wobble a bit and use the carbide expander from Redding ?

Been working for me. And I have been using the old school neck sizer.

bugedp51,

I have a NECO tool, among other concentricity gauges, and don't know what "proof" your photos have provided of anything, other than what you own.

I just rechecked once-fired brass in two different chamberings, deliberately picking some with lop-sided necks to see if I could find this banana-shape caused by firing. None of them showed as much as .001" of run-out when measured just behind the case mouth--unless the neck was dented or flattened slightly. This was exactly how much runout showed up when measuring fired cases from the same batches of brass with under .001" neck thickness variation.

Rifles And More

Remover your expander and size your case, if the runout decreases your expander is the problem.

Also when you full length resize the chambered round is supported by the bolt face in the rear and by the bullet in the throat. With a full length resized case the case body and neck do not contact the chamber. Meaning the case has much less chance of causing bullet misalignment with the bore.

You do not have to believe me but you should be able to trust Kevin Thomas and the late Jim Hull of Sierra bullets testing lab and world class long range shooting competitor.

How well it works depends on how the brass you're using interacts with the die.

I'll use 308 Winchester for example. All following discussion assumes good brass with necks known to be uniform.

My Redding FL die takes the necks down to something like .328"-.329" depending on springback. With thin WW brass the expander ball goes through with a light touch, leaving the necks at .330", and with loaded necks of .332" all is well and runout is low.

The very same die works the hell out of Lapua cases whose loaded necks are .338" in diameter, and runout of sized brass and loaded cartridges suffers as a result.

These are the results no matter what tricks I've applied.

Expander Mandrels and Neck Tension
http://www.accurateshooter.com/technical-articles/reloading/expander-mandrels-and-neck-tension/

FL Bushing Dies vs. Honed FL Dies
http://www.accurateshooter.com/technical-articles/reloading/fl-bushing-dies-vs-honed-fl-dies/


Below is the link to "The Rifleman's Journal" with very good tips on reloading.

The Rifleman's Journal
Index of Articles
http://riflemansjournal.blogspot.com/p/articles-index.html

And below is for the "person" who doesn't think a cases can warp and become banana shaped when fired.



Its bigedp51 and not (bugedp51) even if it bugs you to be wrong.
So read and expand your knowledge on the subject.

Checking Case Wall Concentricity
by Germán A. Salazar
http://riflemansjournal.blogspot.com/2009/07/reloading-audette-neco-case-checker.html

Indexing Cases
by Germán A. Salazar
http://riflemansjournal.blogspot.com/2010/11/reloading-indexing-cases.html

OK Big Ed,

I'm familiar with a bunch of the material you linked to, and also to a lot of other information.

Apparently you didn't notice, but in the article on case warping, nobody could measure any warping after firing until a very tight gauge was made. No significant warpage of fired cases could be found with a NECO tool. Instead the emphasis was on what happened to the case while it was fired.

The easiest way to avoid banana cases, no matter what their cause, is to measure them beforehand to make sure the necks and bodies are as even as possible. This is what many benchrest shooters do, instead of using lopsided cases and indexing them.

You may not have noticed something either: This is the reloading for Big Game Rifles forum, and not even the Long-Range Hunting forum. The minutiae that you're spouting is not only often irrelevant with what your supposed points, but irrelevant to the entire forum. If you want to show off what an expert you are, you might try a forum where somebody cares.