How can I resize the brass before using an expanding mandrel?

[Okie_Poke]

The standard Redding resizing die with Carbide expander is all you need. I used one in several calibers for Decades, with no problems. Don't go making the reloading process more complicated than it needs to be!

Oh, I know I don't need to for my shooting purposes. This is purely a "I want to fiddle with stuff to see if it makes a difference at all" sort of thing.

Edit: Just realized you were responding to the OP and not to me. Never mind. Carry on.

 

[AJC1]

Agree. Standard FL sizing dies, properly set up, work great for hunting rifles. You don't need a mandrel for even virgin brass. I generally run virgin brass through my resizer, with the expander ball, and it works just fine. If you've got pronounced neck dings, you can straighten them out enough to run through your die with a small dowel or a screw driver or somethinge else before resizing the first time. I'm sure the target guys are cringing, but it works fine in a hunting rifle.

But I have some follow up questions for folks about using mandrels. I haven't used them before but am thinking about trying one to test in a target rifle just because. I've done some looking recently, and a couple of OP's comments and questions tied into questions I also have.





My understanding is that the Wilson mandrel, being .001" undersize, is really intended just for virgin brass and that it's not really intended for setting neck tension on fired and resized brass. Is this correct?

For setting neck tension on fired and resized cases, I've seen folks on the interwebs point to 21st Century or Sinclair mandrel dies and the mandrels that are .002" under bullet diameter. However, I see 21st Century has a host of different sizes for each caliber, in half-thousandth increments, and Cortina now offers offer mandrels .002 and .0015 under bullet diameter. I was planning to get a mandrel .002" under bullet diameter to play with, but I don't know what I don't know.

So when selecting a mandrel, which diameter do you usually start with? .002 seems like the default starting point, but is it? When would you use a .001" or .0015" undersized mandrel (or other size) and why? For this rifle, I'm currently using a Redding Type S full length bushing die with the expander ball still in it. If I remove the ball and switch to a seperate mandrel, will I need to adjust which bushing I'm using? I think my current bushing is .002 (maybe .003, I'd have to check my notes) under loaded round OD, and the expander ball is pretty light if it's touching. Would you start with a bushing a size smaller when using a mandrel? Am I way off?

I would expect your current bushing is -.003 to account for spring back after sizing giving a .002 finish press fit. I use a standard forester die and a .002 undersized mandrel giving spring back with slightly more tension. Tuning with neck tension is br territory that I play with but don't have all figured out. Probably ask nature boy or Varminterror on bushings in concert with mandrels. There needs to be enough movement to get plastic deformation not just elastic movement. The state of anneal changes that.

 

[Varminterror]

The irony in these discussions, is really that guys get absolutely wrapped as tight as can be around the axle when they think about mandrel expanding, but how many folks have ever actually measured the diameter of their expander ball, or the resulting ID of their necks after pulling the ball through them?

Mandrel expanding is a grossly better practice than a pull-ball expander, 1st for the functional support the case has during the expanding and the structural design strength of the case which yields more uniform concentricity, and 2nd from the full length contact and support during the expansion. Pushing down against the conical shoulder with the base supported against the shellholder offers greater likelihood of desired result (concentric expansion). We don't have any brass being drawn toward the mouth when we expand by pushing INTO the mouth, whereas we do draw brass forward when we expand with a pull-ball, and any lumps or bumps or thicknesses can kind of guide the case away from centerline, and we end up with odd neck contacts. Equally, we don't have much case neck support with the pull-ball. Expanding with a ball is like watching a snake eat an egg - not all of the case neck is contacting the ball at the same time, so not all of the case neck is being MOVED at the same time, and any springback can allow the necks to be inconsistent and egg shaped - when we drive a full diameter mandrel entirely into the neck, it is supporting the full case neck to ensure uniform and concentric expansion throughout the length of the neck.

From the standpoint of die manufacturing philosophy and product performance, we kinda know that standard dies with pull-ball expanders 1) have exaggeratedly undersized necks to ensure they produce tight enough neck tension on ALL thicknesses (or "thinnesses"?) of brass and produce small enough necks to fit all SAAMI compliant chambers, and subsequently 2) have exaggeratedly undersized pull-ball expanders to ensure that they don't produce loose-fitting necks and unreliable bullet grip. Standard dies are NOT built for controlling neck tension - how many die instructions suggest "run the ram all the way up, screw the die into the press until it touches the shell holder, then lower the ram, screw the die into the press another 1/8-1/4 turn and set the lock ring."? This is the common instruction - why? Because doing so will produce minimal dimension ammunition which should reliably feed and function in any SAAMI compliant chamber (and firearms manufacturers live on the opposite end of the spectrum and want their chambers hugging the upper end of the chamber dimensions so their rifles will swallow any SAAMI compliant ammunition...). But is producing minimal dimension ammo really the best method for sizing brass? Absolutely not - we almost guarantee that doing this will function in any rifle, but we are also almost guaranteeing that the shoulder will be bumping back far more than the 2-3thousandths of an inch it SHOULD be moving to actually match our chamber. Necks and expanders are no different - die manufacturers know they need to make dies which produce ammo which works - I've never seen an accuracy guarantee printed on a die box... So they don't really have to make ideal neck tension - and they can't, because not all brands or lots of brass will have uniform thickness. Making necks too tight has nearly zero consequence for the company - most reloaders won't notice, and they can offer the FREE service of honing necks to the few folks that do notice. But there IS a real consequence for necks too loose, because even novice reloaders will notice when their bullets spin in the necks, or push into the case with finger pressure... So dies are almost always made too TIGHT. I have never had any standard die which I have not custom ordered with a specific neck diameter and expander diameter which produced the neck tension I really want. They're all TIGHT.

Grab an arbor press sometime and feel the difference in seating pressure when you use a standard die with a pull-ball expander vs. using a mandrel expander. Equally, run your press arm slowly enough to feel the difference in expanding pressure with a mandrel expander after sizing one case with a standard die and the other case with a properly sized bushing die... Even without pin gauges, you can feel the difference in the dimensions produced by the different gear, because you can FEEL the difference in how far you're moving the brass during these steps.

But for 1) low volume ammo, 2) hunting ammo with low performance demand, and 3) ammo being made with capital cost prioritized over performance, standard dies with tight necks and pull-ball expanders will do the job just fine.

 

[westernrover]

Wouldn't the push-mandrel also resize the neck without all of the case neck contacting the mandrel at the same time? When we push it in, it's sizing as it's going in. It's true that the neck behind the tip of the mandrel can't shrink back down, but the neck ahead of it is still smaller. What do you think of the Lee Collet dies? They have a mandrel also, but the whole mandrel is inserted all the way through the neck before the neck is pressed down onto the mandrel by the collet fingers. I know some people swear by them, but they don't seem to be popular in competitive shooting.

 

[westernrover]

Up to this point, I've used Redding Type-S bushing dies. I don't own any regular FL dies for rifle cartridges so I couldn't describe how they work.

As an example, my .223 Remington die uses a Short Action Customs bushing that sizes my Lake City brass neck down to an ID of .221". Then the Redding carbide expander ball (which measures .222") is pulled through leaving an ID of .222". When I seat .224" bullets, they have 2 thou of neck tension.

If I were to remove the carbide pull button and use a push mandrel, what size should I use? If I were to order the standard Wilson or 21st Century mandrel for 22 caliber, it would be .223" Would that hold my bullets securely enough even if I didn't crimp?

I want to get into expanding mandrels (hence this thread), because I believe the arguments that you've described with respect to their superiority over pull-balls. If I go with the standard 1 thou under mandrels, is that going to work in my autoloader magazines and feed-ramps? I have the same questions as Okie Pokie -- what are some reasons I'd want to be 1 thou under, or 1.5 thou under or 2 thou under and ultimately, which mandrels do I want?

I know from my experience described in an earlier post that 1 thou under was too loose. 2 thou under is what my pull-buttons and Lee Collet die generate and it works. But then why are the standard mandrels only 1 thou under? What am I missing?

 

[AJC1]

Up to this point, I've used Redding Type-S bushing dies. I don't own any regular FL dies for rifle cartridges so I couldn't describe how they work.

As an example, my .223 Remington die uses a Short Action Customs bushing that sizes my Lake City brass neck down to an ID of .221". Then the Redding carbide expander ball (which measures .222") is pulled through leaving an ID of .222". When I seat .224" bullets, they have 2 thou of neck tension.

If I were to remove the carbide pull button and use a push mandrel, what size should I use? If I were to order the standard Wilson or 21st Century mandrel for 22 caliber, it would be .223" Would that hold my bullets securely enough even if I didn't crimp?

I want to get into expanding mandrels (hence this thread), because I believe the arguments that you've described with respect to their superiority over pull-balls. If I go with the standard 1 thou under mandrels, is that going to work in my autoloader magazines and feed-ramps? I have the same questions as Okie Pokie -- what are some reasons I'd want to be 1 thou under, or 1.5 thou under or 2 thou under and ultimately, which mandrels do I want?

I know from my experience described in an earlier post that 1 thou under was too loose. 2 thou under is what my pull-buttons and Lee Collet die generate and it works. But then why are the standard mandrels only 1 thou under? What am I missing?

Your missing spring back. A metal yields at plastic deformation but still springs back if it also has elastic properties.

 

[Walkalong]

We always end up with more than one bushing. First we guess wrong on the first one we buy (Murphy's law),
then we get another, then we change brass, necks are a little thicker/thinner.........

6MM bushings. And I have a .265 now as well.

then

 

[westernrover]

Spring back or not, the balls and collet die mandrel I have that work are 2 thou under. I don't have pin gauges, but measuring the OD, I can verify they size the ID to 2 thou under bullet diameter. I would assume the larger push mandrel that is 1 thou under, would size to 1 thou under.

 

[westernrover]

I collected more bushings when I was trying to get the neck diameter where I wanted it without using a ball, collet die or mandrel. I just ran the neck into the bushing and hoped it came out the right size. It would provided I wasn't sizing it down too far. Otherwise, I found I had to size it down in steps with an intermediate bushing. If I did that, then it would come out of the final bushing the OD that was printed on the bushing. I only ever use one kind of brass for any cartridge, so I've never needed more bushings for various headstamps.

What is the result of sizing the necks with a bushing only? A lot of people have supposed that it pushes the inconsistencies to the ID. Some have supposed it works if you turn the necks. I don't know.

 

[AJC1]

We always end up with more than one bushing. First we guess wrong on the first one we buy (Murphy's law),
then we get another, then we change brass, necks are a little thicker/thinner.........

6MM bushings. And I have a .265 now as well.
View attachment 1187782
then

Do I spy a collection of sac bushings... they have a great reputation. Don't have any yet.

 

[JFrank]

Up to this point, I've used Redding Type-S bushing dies. I don't own any regular FL dies for rifle cartridges so I couldn't describe how they work.

As an example, my .223 Remington die uses a Short Action Customs bushing that sizes my Lake City brass neck down to an ID of .221". Then the Redding carbide expander ball (which measures .222") is pulled through leaving an ID of .222". When I seat .224" bullets, they have 2 thou of neck tension.

If I were to remove the carbide pull button and use a push mandrel, what size should I use? If I were to order the standard Wilson or 21st Century mandrel for 22 caliber, it would be .223" Would that hold my bullets securely enough even if I didn't crimp?

I want to get into expanding mandrels (hence this thread), because I believe the arguments that you've described with respect to their superiority over pull-balls. If I go with the standard 1 thou under mandrels, is that going to work in my autoloader magazines and feed-ramps? I have the same questions as Okie Pokie -- what are some reasons I'd want to be 1 thou under, or 1.5 thou under or 2 thou under and ultimately, which mandrels do I want?

I know from my experience described in an earlier post that 1 thou under was too loose. 2 thou under is what my pull-buttons and Lee Collet die generate and it works. But then why are the standard mandrels only 1 thou under? What am I missing?

Mandrels come in several sizes, if you’re dead set on trying them , you could order them up to .004 under a bullet diameter. It really isn’t that difficult to test which is gives optimum performance in your rifle. Myself, I’ve done quite a bit of testing in this area and personally I don’t use them for settling neck tension in my hunting rifles or competition rifles. I found that 5/10,000 increments are just not necessary and it will take a very accurate rifle to even see a difference in a .001 increment at mid range, unless of course your trying to use a ridiculously light amount of neck tension and then you would see erratic groups on paper. When asked how much bullet hold to start with, I would start with plenty …

 

[JFrank]

I collected more bushings when I was trying to get the neck diameter where I wanted it without using a ball, collet die or mandrel. I just ran the neck into the bushing and hoped it came out the right size. It would provided I wasn't sizing it down too far. Otherwise, I found I had to size it down in steps with an intermediate bushing. If I did that, then it would come out of the final bushing the OD that was printed on the bushing. I only ever use one kind of brass for any cartridge, so I've never needed more bushings for various headstamps.

What is the result of sizing the necks with a bushing only? A lot of people have supposed that it pushes the inconsistencies to the ID. Some have supposed it works if you turn the necks. I don't know.

You do not have to turn necks to use bushings only, the minute difference in neck thickness will not show on paper unless you are shooting long range.
I can post a couple of examples if you want

 

[Click_Here]

The irony in these discussions, is really that guys get absolutely wrapped as tight as can be around the axle when they think about mandrel expanding, but how many folks have ever actually measured the diameter of their expander ball, or the resulting ID of their necks after pulling the ball through them?

This is what I was going to ask. Im intrigued by the whole NekkTenshenns thing but I didnt go all crazy and buy before I try. When my 6.5 dies come in. Im going to measure the expander ball and ID of the brass on a sized case and see if what I get is what I can work with. No doubt i'll be getting all this down the road, something will force it. Low SD or smaller groups...something....free shipping coupon....

 

[BBarn]

On a related note, I've removed the decapper/expander from a regular FL die, sized the case, re-installed the spindle and run the sized cases in part way to expand the neck with a pushing motion rather than a pulling motion. Haven't tried to measure any differences, but it's not difficult to do and can be done with a standard FL sizing die.

 

[westernrover]

Mandrels come in several sizes, if you’re dead set on trying them , you could order them up to .004 under a bullet diameter. It really isn’t that difficult to test which is gives optimum performance in your rifle. Myself, I’ve done quite a bit of testing in this area and personally I don’t use them for settling neck tension in my hunting rifles or competition rifles. I found that 5/10,000 increments are just not necessary and it will take a very accurate rifle to even see a difference in a .001 increment at mid range, unless of course your trying to use a ridiculously light amount of neck tension and then you would see erratic groups on paper. When asked how much bullet hold to start with, I would start with plenty …

You do not have to turn necks to use bushings only, the minute difference in neck thickness will not show on paper unless you are shooting long range.
I can post a couple of examples if you want

I read your posts and #21 as well. Are you saying that you FL size with a bushing and then don't use a ball or mandrel?
I did that with 6.5 Grendel and my bushing resulted in 1 thou hold. It was too little and I got setback. But it seems you're suggesting starting with plenty of hold.

Suppose I take the ball out of my 223 Remington die. I'd have 3 thou hold. I know you can only speculate, and I can actually test it myself, but would you suppose 3 thou bushing-only hold would be better than 2 thou after the pull-ball? How would you do it?

My virgin Nosler brass for the hunting rifle is 4 thou under. Would you just load it up like that or push it open? how much?

The fired Nosler brass is 4 thou over bullet diameter. If I were to use a bushing only to size the necks, how far down should I go?

 

[JFrank]

No mandrels, no expander ball’ In general, I start with measuring the OD of a loaded round, in my case that’s .265 from there I select bushings 2-3-4-5 under that number for testing. In my rifle .002 under results in erratic and inconsistent grouping at mid range while .003 ( .262) shoots much better as posted below at 300 yards during barrel break in. now let’s take this out to 500 yards as below and compare against .004 under a loaded round ( .261) bushing in a charge / powder ladder format so I can see the load coming into and out of tune. it’s gets pretty obvious which bushing or how much hold the rifle likes by judging the overall performance in a highly accurate platform.
Point is that if you’re close in hold/neck tension or have a bit extra you won’t see the difference at even 300 yards and the node doesn’t really move just gets more consistent and of course smaller. I like to test bushings early in the load development as the groups are just easier to interpret. Not all combinations like more.. you just have to test a bit IF you decide want to go down this rabbit hole.

 

[JFrank]

When guys start talking about using mandrels .001 under or .0015 neck tension and trying to calculate spring back it’s just not something that is practical and quite possibly detrimental to performance.

 

[AJC1]

When guys start talking about using mandrels .001 under or .0015 neck tension and trying to calculate spring back it’s just not something that is practical and quite possibly detrimental to performance.

I don't dabble under .002 and if it's an autoloader more likely. 003. Soft seating was a thing for a few years, but that's before my time.

 

[JFrank]

I don't dabble under .002 and if it's an autoloader more likely. 003. Soft seating was a thing for a few years, but that's before my time.

Yep’ when Guys ask me I say start with plenty, if it’s too much than the target will let you know real quick .. that soft seating guys use to do was more a short range thing and doesn’t work very well at long range, @ walk along could expand on the short range aspect

 

[243winxb]

A Redding non-bushing FL die is $55, but what will it do to my necks?

To find out.......

Measure the outside diameter of the necks. 3 ways

1. Sized, No expander.

2. Sized with expander.

3. Sized & bullet seated.

This will show if brass necks are being over worked.

Aim for .002" neck tension.

 

[Varminterror]

What do you think of the Lee Collet dies?

What do I personally think about them? Well… I wish all of my competitors used Lee Collet Dies.

BIG hint: nobody else in the market is making them. If it were a good idea, everyone else WOULD be making them…

 

[Varminterror]

On a related note, I've removed the decapper/expander from a regular FL die, sized the case, re-installed the spindle and run the sized cases in part way to expand the neck with a pushing motion rather than a pulling motion. Haven't tried to measure any differences, but it's not difficult to do and can be done with a standard FL sizing die.

The ball doesn’t fully support the neck, so as you push the ball fully to the bottom of the neck, the top is allowed to contract above the ball in natural springback, so when you withdraw the ball, you’re still pulling up on the shoulder - without any kind of case support - and redrawing the diameter of the neck during the pull stroke.

Think about pulling an egg out of a snake vs pulling a post. The egg has to force elastic expansion as it is drawing out PLUS the friction of the wall, whereas the post only fights the friction. One is reshaping the snake along the way, one is not.

 

[Walkalong]

When guys start talking about using mandrels .001 under or .0015 neck tension and trying to calculate spring back it’s just not something that is practical and quite possibly detrimental to performance.

I could care less about what .??? neck tension I have. I know what seating force generally works from testing, but every time I work up a load in something I play with neck tension. Too little and the numbers won't be as consistent (ES/SD's not as good/accuracy suffers). Too much and you can start seeing inconsistent numbers/a wider range on the concentricity gauge. .001 to .002 runout consistently is better than .0002 to 3.0.

Low ES/SD numbers don't guarantee a load will shoot, but it does let us know vertical dispersion down range should be good, and low concentricity numbers don't guarantee a load will shoot, but we do want good numbers for both of those for a powder/primer/bullet combo our gun likes.

 

[Kaldor]

We always end up with more than one bushing. First we guess wrong on the first one we buy (Murphy's law),
then we get another, then we change brass, necks are a little thicker/thinner.........

6MM bushings. And I have a .265 now as well.
View attachment 1187782
then

Nice! I have a small collection of the SAC bushings. I do prefer them over the Reddings I also have.

Do I spy a collection of sac bushings... they have a great reputation. Don't have any yet.

Buy with confidence! I use them in my Redding and Hornady bushing dies. They work very nicely.

 

[Kaldor]

I use a mix of FL and FL bushing dies from Hornady and Redding with SAC and Redding bushings, in combination with a Sinclair mandrel that is 2 thou under bullet size. It markedly increased my accuracy over an expansion ball/button/whatever. Its just more consistent.

What @Varminterror said is spot on and is the reason "why" mandrel sizing is the norm not the exception when you are really chasing accuracy.