Mandrel vs Expander button in a die

[Hohn]

Ed, I think you are misunderstanding my point. I'm not saying a variation in 0.009 of neck thickness across cases and headstamps. I'm saying that an actual thickness of 0.009" wall is about how thin a neck would have to be to need a .240 ID neck in the die. That's a very thin neck. Let's say your loaded case diameter is .242. That's only .018 over bullet size, or 0.009 per side.


Do you have any .223 cases that are under .243 loaded neck diameter? That would be uncommon. For reference, the tightest Shilen neck offered in .223 is 0.246 and that assumes a turned neck.

This is why the .240 Forster diameter is needlessly tight and overworks the neck brass.

I do not neck turn and have no intentions of ever doing so.


Forster is saying that variations in neck thickness from one brass or case to another-- NOT variations in thickness within a single case. I'm sure that you have a lot of thickness variation in a large sample of mixed brass. I had my die honed to a size that works for me because I'm using all cases of one make that have pretty consistent necks. And any cases of different brand that I use are thicker wall, so my die still works.

You are correct, because of your mixed brass and SAAMI chambers, you do not need a honed die.


I understand you prefer to follow the Redding guidance, but it's not applicable for the Forster honed die for two reasons:
-- The Redding setup uses a floating bushing that cannot force the neck to be concentric. The forster honed neck is concentric to the case walls and cannot move.
-- Variations in neck wall thickness may displace a Redding bushing. But they cannot do that in a Forster die. The worst case is that you will have variations in springback in the thicker areas. But this cannot be addressed with a die of ANY kind-- honed or not, expander or not. The only way to address neck thickness variation is neck turning. Although I will say that the Lee Collet Die does seem to improve things a little bit if you rotate the case within it and cycle it multiple times ("ironing" the neck). I've not seen conclusive proof of the LCD actually reducing neck wall variation, but many seem to believe it can.

Lots of us are using honed Forsters with excellent concentricity regardless of whether we neck turn or not. The forster expander works well, and some users are reporting that the mandrel method works even better, at the cost of an extra step.

 

[Uncle Ed]

You are correct, because of your mixed brass and SAAMI chambers, you do not need a honed die.

Thank you for telling me something I already know, In the 6.5 Guys video they are using Lapua brass with their honed Forster die.

And my Forster .223 bushing bump die came with three bushings .247", .245", .243" diameter. I just sized a few LC 5.56 case with my Forster .223 die with the expander removed. And the sized neck measured .2415 and with the expander installed the neck diameter was .244. So I would not consider this overworking the brass and perfect for brass that is not neck turned.

And this closely matches what Redding recommends below for unturned brass and using their expander.

Tech Line & Tips (FAQs)
Bushing Selection

The easiest way to determine the proper diameter bushing is to measure the neck diameter of several loaded or dummy cartridges with an accurate micrometer. (These dummy cartridges can be loaded with your old set of dies or a borrowed set.) Then, simply subtract 0.001" from the cartridge that had the smallest average measurement. This will allow for a slight amount of spring back and create a proper press fit for the bullet.

The above methods of determining bushing size require that the cases being sized have a fairly uniform neck wall thickness or have been neck turned. If the neck wall thickness varies more than 0.002", it may be necessary to use a bushing a couple of thousandths smaller than your calculations indicate, and then use a size button in the die to determine the final inside neck diameter.

And I did not misunderstand your statement about .009 neck thickness. My Lake City 5.56 brass has an average neck thickness of .010 to .012. And again I have Remington cases with .009 neck thickness variations and are used as blasting ammo in my AR15. And again I'm loading for three AR15 rifles and two .223 bolt actions. And I sort the cases with a Redding neck thickness gauge and use the most uniform cases in the bolt actions and my AR15 HBAR.

And since all my brass has neck thickness variations of .002 or more I do not need a Forster honed die. And my Forster dies still produces the least amount of neck runout than any other type die that uses a expander. Meaning it is the Forster high mounted floating expander that makes the difference.

 

[dolek]

These threads sure die a horrible death...

 

[INTJ]

When I start gearing up for a new caliber I buy a bushing type die for sizing. The first thing I do after opening the die box is remove the expander button and put it in the box where it will stay until I decide to sell that die.

There is absolutely no way that an expander button can do as good a job as a mandrel. If you think about it of a bit it is obvious why. The button works much like an egg going through a snake. A mandrel is like a snake swallowing a piece of pipe.

IMO you would benefit from this video

Joe

I have missed something on this thread and I should clarify. Not all expanders in sizing dies are the same. Whidden expanders are mandrels that fit in their sizing die. For me they have been the ultimate solution. Seating force as measured by a hydro seater press is much smoother and more consistent than using only a bushing.

I only use that for competition rifles. For hunting rifles I just use a FL die
with its button expander and all, bump the shoulders .002ish, and load 'em up. Much of the detailed loading methods used for high accuracy competitions don't make much difference in a hunting rifle.

 

[Uncle Ed]

Below is a closeup macro photo of a RCBS .243 expander that badly needs to be polished. And I can understand why some reloaders do not want to drag a rough expander through their case necks. But even a expander like the one below can be polished smooth and lubing inside the case neck works wonders and lowers drag.

Below is a Whidden expander and they are not shaped like expander mandrels.

with average scopes. That my opinion at 69 with chronologically gifted eyesight and spending money on reloading equipment

Below is my Redding .243 FL die that I equipped with a Forster expander ball assembly. And the Redding expander is on the left has much more surface area and I can understand why some reloaders do not like to use Redding expanders. "BUT" the Forster expander ball has far less area contacting the case neck with far "LESS" drag.

All my rifles are off the shelf factory rifles with SAAMI chambers, and I do not have any Lapua brass and do not shoot in competition. I have Sinclair and Lyman type "M" expander dies and see no decrease in neck runout vs using the Forster dies with their expanders.

I do not think using a good polished expander ball is the end of the world. And the 6.5 Guys stated they got less runout using a Forster die vs their Redding dies. And a little case lube inside the case neck greatly reduces expander drag and pull on the neck.

And the cheap Lee die below produced less neck runout than a Redding bushing die using its expander. Meaning bushing dies work best with tight neck chambers and neck turned brass.

Bottom line, many of you competitive shooters may see a difference with your custom rifles and your sizing methods. But with my factory rifles with SAAMI chambers, bushing dies, expander dies, neck turning and a multitude of gauges did not make my rifles shoot any better. Meaning much of what benchrest shooters do will not have any effect on a factory rifle with SAAMI chambers. But I'm 69 and have chronologically gifted eyesight and drink too much coffee and wish I had laser guided bullets.

 

[INTJ]

The Whidden is MUCH more like an mandrel than a typical button. It has a smooth even diameter section at the top. More importantly, it's works exceptionally well and how something actually works trumps our theory and speculation every time.

 

[AJC]

The Whidden is MUCH more like an mandrel than a typical button. It has a smooth even diameter section at the top. More importantly, it's works exceptionally well and how something actually works trumps our theory and speculation every time.

How something actually works requires evidence otherwise it's also just option. Standing by for evidence or test results.

 

[Hohn]

Ironically, Ed keeps pointing to the 6.5 guys video as evidence of why the Forster high-mounted expander is awesome, yet the video shows the dies with no expander installed. And if you listen to the actual dialogue, you'll here them say @ 2:08 "it's predicated on you using a mandrel or expander ball to bring it up."

In other words, the video he's citing to tout the virtue of the Forster expander actually suggests they are using their honed Forsters without the expander.


I have nothing against the Forster expander assy and I think the Forster sizer is the best overall approach (obvious, I've bought them and paid extra for honing). They work and work well.

But that doesn't mean a mandrel can't be better in some instances.

 

[INTJ]

How something actually works requires evidence otherwise it's also just option. Standing by for evidence or test results.

I am not going to video myself seating bullets on my Hydro Seater, both with and without use of the Whidden expander, just to prove something on an internet forum. If you will not take my word for it and/or try it yourself then too bad for you.........

 

[Uncle Ed]

Ironically, Ed keeps pointing to the 6.5 guys video as evidence of why the Forster high-mounted expander is awesome, yet the video shows the dies with no expander installed. And if you listen to the actual dialogue, you'll here them say @ 2:08 "it's predicated on you using a mandrel or expander ball to bring it up."

In other words, the video he's citing to tout the virtue of the Forster expander actually suggests they are using their honed Forsters without the expander.

Actually what they said and did in the video was what Forster recommended. And that was to measure loaded rounds neck diameter and subtract .004 and have the dies neck honed to that diameter.

They then said to use an expander die or the Forster dies expander to bring the neck up to the proper diameter. And my Forster .223 dies expander is only expanding the neck .0035 without having a honed neck with unturned Lake City brass.

And this corresponds with what the Redding bushing die FAQ tells you. And to use a smaller bushing and use their expander if you do not neck turn and the neck thickness varies .002 or more.

And the reason I posted the 6.5 Guys video is because the Forster die produces less neck runout using their expander than a bushing die with no expander.

And the best part about reloading is the person pulling the press handle decides how to do it.

 

[AJC]

Ironically, Ed keeps pointing to the 6.5 guys video as evidence of why the Forster high-mounted expander is awesome, yet the video shows the dies with no expander installed. And if you listen to the actual dialogue, you'll here them say @ 2:08 "it's predicated on you using a mandrel or expander ball to bring it up."

In other words, the video he's citing to tout the virtue of the Forster expander actually suggests they are using their honed Forsters without the expander.


I have nothing against the Forster expander assy and I think the Forster sizer is the best overall approach (obvious, I've bought them and paid extra for honing). They work and work well.

But that doesn't mean a mandrel can't be better in some instances.

I believe a mandrel is better because it gives you more options. Just like bushings , you can adjust them in very small quantities. I cant sell that as fact but if you want to tune neck tension its easier to run more tests.

 

[David101]

I just cant understand how the bushing dies work with expaneders or mandrels. The expander or manderl is going to be the first thing in and the last thing out. The bushing is going to reduce the neck as a function between these two actions.
So once your case is fired the neck will naturally be on the larger size. To me this means that it only needs to be reduced. Hence a bushing is only needed or a Lee collet die to reduce the size of the neck.
Can someone please explain if I have this wrong and why an expander would be needed or helpful?

 

[AJC]

I just cant understand how the bushing dies work with expaneders or mandrels. The expander or manderl is going to be the first thing in and the last thing out. The bushing is going to reduce the neck as a function between these two actions.
So once your case is fired the neck will naturally be on the larger size. To me this means that it only needs to be reduced. Hence a bushing is only needed or a Lee collet die to reduce the size of the neck.
Can someone please explain if I have this wrong and why an expander would be needed or helpful?

You size the neck down in the die. You set final deminsion with the expander ball or mandrels. If you have turned necks its easier to just skip the second step.

 

[Uncle Ed]

I just cant understand how the bushing dies work with expaneders or mandrels. The expander or manderl is going to be the first thing in and the last thing out. The bushing is going to reduce the neck as a function between these two actions.
So once your case is fired the neck will naturally be on the larger size. To me this means that it only needs to be reduced. Hence a bushing is only needed or a Lee collet die to reduce the size of the neck.
Can someone please explain if I have this wrong and why an expander would be needed or helpful?

If the neck is not turned the bushing will push the neck thickness variations to the inside of the neck. And using the expander will push the neck thickness variations to the outside of the case neck.

Tech Line & Tips (FAQs)
https://www.redding-reloading.com/tech-line-a-tips-faqs/140-bushing-selection
Bushing Selection

The easiest way to determine the proper diameter bushing is to measure the neck diameter of several loaded or dummy cartridges with an accurate micrometer. (These dummy cartridges can be loaded with your old set of dies or a borrowed set.) Then, simply subtract 0.001" from the cartridge that had the smallest average measurement. This will allow for a slight amount of spring back and create a proper press fit for the bullet.

If you're starting with new cases, the neck wall thickness can be determined as above with a ball micrometer, or you can seat boat-tail bullets in a few cases and measure their neck diameter. Generally, the neck diameter of new cases is small enough to hold a bullet without sizing. As a last resort, you can measure the neck wall thickness of the cases with a caliper. Be aware that you may not select the correct bushing on the first try when using a caliper to measure neck wall thickness, due to the reduced measuring accuracy of the caliper.

The above methods of determining bushing size require that the cases being sized have a fairly uniform neck wall thickness or have been neck turned. If the neck wall thickness varies more than 0.002", it may be necessary to use a bushing a couple of thousandths smaller than your calculations indicate, and then use a size button in the die to determine the final inside neck diameter.

Tech Line & Tips (FAQs)
https://www.redding-reloading.com/tech-line-a-tips-faqs/146-concentricity-problems
Concentricity Problems
a.k.a Neck Runout With Bottleneck Cases

We have conducted many tests over the years on the various factors contributing to concentricity problems with bottleneck cases. We have repeatedly found a definite correlation between the uniformity of the brass (or lack of it) and the resulting concentricity of the neck to the body of the case.

An interesting experiment also revealed that neck turning of brass that was intentionally sorted as non-uniform, showed little or no concentricity improvement when used in standard S.A.A.M.I. spec chambers. Conversely brass that was sorted and selected for uniformity remained uniform and concentric with or without a neck turning operation.

 

[INTJ]

I just cant understand how the bushing dies work with expaneders or mandrels. The expander or manderl is going to be the first thing in and the last thing out. The bushing is going to reduce the neck as a function between these two actions.
So once your case is fired the neck will naturally be on the larger size. To me this means that it only needs to be reduced. Hence a bushing is only needed or a Lee collet die to reduce the size of the neck.
Can someone please explain if I have this wrong and why an expander would be needed or helpful?

I have found that in neck turned cases using a quality expander--like what Whidden offers, makes seating smoother and seating pressure more consistent. That is what I have seen while using a 21st Century Hydro Seater that measures the PSI required to seat cases.

Whidden and some other companies offer excellent expanders for the dies that come in .001" size increments. So what you do is pick a bushing that sizes
the neck down the minimum amount required for the selected expander.

I only bother with all this for my competition rifles. For hunting rifles I just use a standard FL die with an expander, usually Forster or Redding, bump the shoulder a couple thousandths, crimp the necks with a Lee crimp die, and go hunt.

 

[Iowa Fox]

I'm loading for three AR15 rifles and two bolt action .223 rifles. And my Forster .223 die does not have a tight neck.

Below are just some of my .223 dies I used and tested over the years, and I prefer using the Forster die with its expander.
So yes I have .223 dies and I did not have my Forster dies neck honed because I want to be able to size different brands of brass. But that doesn't mean if you use one brand of case you can have the neck honed.

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

Forster FL dies, necks honed to .265″, .266″, and .267″.

Are Your Sizing Dies Overworking Your Rifle Brass?
http://www.massreloading.com/dies_overworking_brass.html

Table 2 - Inside Diameter Measurements for 5 different sizing dies

In the chart above the two RCBS .223 dies varied .005 in neck diameter. Meaning chambers and dies vary in size and nothing is written in stone.

Ed, I thought I was alone in my collection of 223 dies. If you add Wilson arbor press dies, couple sets of Dillon, Lyman, and a set of Redding competition Type S full length we have exactly the same stack.

Every single set does a little bit different job. I like the Lyman set for its seater die and the different Lyman steating stems I have for my cast bullets.

A guy could go broke just trying different dies.

 

[Uncle Ed]

Ed, I thought I was alone in my collection of 223 dies. If you add Wilson arbor press dies, couple sets of Dillon, Lyman, and a set of Redding competition Type S full length we have exactly the same stack.

Every single set does a little bit different job. I like the Lyman set for its seater die and the different Lyman steating stems I have for my cast bullets.

A guy could go broke just trying different dies.

I worked part time in a sporting goods store and got very good discounts. I even got free items if I answered factory questionnaires. My photo didn't have all my .223 dies, I didn't want to look like I had excessive compulsive disorder.

 

[bozo699]

I worked part time in a sporting goods store and got very good discounts. I even got free items if I answered factory questionnaires. My photo didn't have all my .223 dies, I didn't want to look like I had excessive compulsive disorder.

And you think your long detailed posts don’t already point to that fact?.....not being mean I fit in that same boat
Wayne

 

[INTJ]

Most of us on this thread have obsessive compulsive disorder. I will not comment of the number of dies I have for any one cartridge........

 

[Iowa Fox]

I worked part time in a sporting goods store and got very good discounts. I even got free items if I answered factory questionnaires. My photo didn't have all my .223 dies, I didn't want to look like I had excessive compulsive disorder.

I have a sneaking hunch a lot of us on here have excessive compulsive disorder. In my opinion there is no substitute for empirical experience.