Expander Mandrels and Neck Tension

[Newton]

Greetings

Anyone using something like this

Expander Mandrel

Is it worth the extra added expense ?

[Tripodmvr]

I invested in Lee Collet neck sizing dies and they also ensure round necks with the same amount of 0,002 neck tension. The major benefit is the fact that no lube is necessary and makes for very fast resizing of your cases.

[janfred]

Greetings

Anyone using something like this

Expander Mandrel

Is it worth the extra added expense ?

Depends on what you want to do.

Using quality brass with reasonably constant neck wall thickness few would see any improvement over using a normal bushing type die.

If brass quality is not that great and/or you just have access to a normal sizing die, removing the expander ball then using a mandrel can improve the run-out and set neck-tension to your preference. May also reduce the ES/SD numbers.

In most cases you would only see a difference if the shooter and rifle is capable of shooting really tight groups.

It is 3 extra steps. Lube inside neck, use the mandrel then clean inside case.

[Newton]

I think an idea might be to use a - FORM die first , and then after that the Lee neck size collet die.

A FORM die is basically a FL size die with the whole  de-capping and expander ball rod assembly not present
It is then easier ( if necessary )  to hone / open the neck portion slightly so that the neck is not sized too tight / small.

Body and Forming Dies

[Tripodmvr]

The simplicity of the collet die is what appeals to me and it has proven itself when it comes to accuracy. Remember that the the die forms the neck to 0.001/2 smaller than bullet diameter. If you use the form die it will have to force the neck open if it is smaller than that. To keep it simple you want less steps in the process and not more. Preparing cases is the most time consuming task.

[janfred]

I only know of one target rifle shooter in the western cape that uses an after-market mandrel. He is not one of the top shooters.

I do not know of any Bisley target rifle shooters in SA that attends the SA open every year that uses a collet die. I don't know all of them, but I am acquainted with the top 100 or so.

Maybe they use them in other disciplines...

[Treeman]

https://www.google.co.za/search?q=collet+dies+++eric+cortina&hl=en-ZA&sxsrf=APwXEdfqJ_1NqBIPNhLwT0HjaFsXOSn2pw%3A1682271471553&ei=72xFZJmuIcOW8gK484XYCw&ved=0ahUKEwjZ4ejLxcD-AhVDi1wKHbh5AbsQ4dUDCBA&oq=collet+dies+++eric+cortina&gs_lcp=Cgxnd3Mtd2l6LXNlcnAQDDoGCAAQFhAeOggIABCKBRCGAzoFCCEQoAE6CAghEBYQHhAdOgQIIRAVOgcIIRCgARAKOgUIABCiBDoICAAQCBAHEB46CggAEAgQBxAeEAo6CggAEAUQBxAeEApKBAhBGABQAFiItAFg27sBaABwAXgAgAGcA4gBmTiSAQgyLTE4LjYuMZgBAKABAcABAQ&sclient=gws-wiz-serp#fpstate=ive&vld=cid:6c5b87a8,vid:lLG2kSrD40g

I like referring to this guys opinions.

[big5ifty]

I use the expander mandrels.

Helps for reloading consistency.

I removed all the decapping rods from my target rifle dies, I found that if the rod is not perfectly straight, it draws the expander ball out at an angle.

You'll need a universal decapping die as well.

If you find you need a bit more neck tension, it's just an additional size mandrel.

[jager]

I think an idea might be to use a - FORM die first , and then after that the Lee neck size collet die.

A FORM die is basically a FL size die with the whole  de-capping and expander ball rod assembly not present
It is then easier ( if necessary )  to hone / open the neck portion slightly so that the neck is not sized too tight / small.

Body and Forming Dies

I use a Redding body die to bump the shoulders back, followed by a lee collet die for the necks.  The body die leaves the necks completely untouched, and the collet die sizes them perfectly and keeps everything concentric.  Expander balls skews the case necks, and kills any chance you had of making concentric loads.

Expander mandrels will give you better concentricity than an expander ball. But IMHO the lee collet die does even better. It works your brass less, and costs less, and you don't need to use lube.

[Newton]

I only know of one target rifle shooter in the western cape that uses an after-market mandrel. He is not one of the top shooters.

I do not know of any Bisley target rifle shooters in SA that attends the SA open every year that uses a collet die. I don't know all of them, but I am acquainted with the top 100 or so.

Maybe they use them in other disciplines...

SO
These top competition shooters
What reloading procedures do they use ?
With what equipment ?

[Newton]

The simplicity of the collet die is what appeals to me and it has proven itself when it comes to accuracy. Remember that the the die forms the neck to 0.001/2 smaller than bullet diameter. If you use the form die it will have to force the neck open if it is smaller than that. To keep it simple you want less steps in the process and not more. Preparing cases is the most time consuming task.

The way I understand it is that the FL sizing die will initially size the neck too small
So that the expander ball can open up the neck on the return stroke
Remove the expander ball and the neck remains slightly too SMALL ( although you have now "bumped" the shoulder )
You can of course use a  FL BUSHING sizing die - but - these do not fully to the full length size the neck and can leave you with "donuts'
A form die properly measured and modified will "bump"the shoulder without sizing the neck too small
( if at all ? )
There is then less work for the LEE collet die to do
Another step but much less working of the brass.

Even if one ONLY uses the LEE neck sizing collet die there will come a time when a FL resize will be need to be used.

All depends on how your rifles chamber was cut .. competition ( tight ) no-turn-neck / long throat and so on

[janfred]

I only know of one target rifle shooter in the western cape that uses an after-market mandrel. He is not one of the top shooters.

I do not know of any Bisley target rifle shooters in SA that attends the SA open every year that uses a collet die. I don't know all of them, but I am acquainted with the top 100 or so.

Maybe they use them in other disciplines...

SO
These top competition shooters
What reloading procedures do they use ?
With what equipment ?

Flavour of the dacade is Redding Type S Competition die set with a full-length sizing die. Wilson press-mounted dies are also becoming more in use. A few Forster dies as well. All of them are bushing dies.

Lapua .308Win cases. A few have neckturned their cases because they are using 0.340" neck chambers.

Berger Fullbore 155.5gr bullets.
Sierra 2156, Lapua Scenar and Berger VLD also represented. No one uses any flavour of Hornady.

Presses are diverse with Forster Co-ax, Rock-chuckers that I know of, but presses are not mentioned much. A few still use Lee presses.

CCI Br2 seems to be the primer of choice, followed by CCI200, Federal and S&B.

Rifle chambers are custom cut for personal preference. Usually body diameter is at minimum SAAMI diameter. Neck and freebore is below SAAMI diameter with feeebore anything from 0 to 0.050"

Powder is Varget, N140, S335, S355. Some may use other, but then they must be too shy to talk about it.

Procedures for loading are pretty diverse as well. The basic procedures are the same. Clean, lube and deprime, clean off the lube and clean primer pockets, charge and seat the bullets. Some wet-tumble, some dry-tumble, some do not clean primer pockets. 0.001" to 0.003" shoulder bump, neck-tension. Provided you follow your procedure consistently, the ammo shoots the same. At least, on our targets.

Barrels are Krieger, Brux, Border, Lothar Walther to name a few. 30-32" long and cut with a custom chamber reamer.

Actions are mostly Barnard-P with a few Millenium and an Inch action or two. RSA actions are also used but are becoming fewer every year.

[Newton]

Powder is Varget, N140, S335, S355. Some may use other, but then they must be too shy to talk about it.

Barrels are Krieger, Brux, Border, Lothar Walther to name a few. 30-32" long and cut with a custom chamber reamer.

Actions are mostly Barnard-P with a few Millenium and an Inch action or two. RSA actions are also used but are becoming fewer every year.

Thanks
So .. no SOMCHEM and no RSA barrels
The RSA actions were the Musgrave on the single shot competition rifle ?

[Newton]

Here is Redding

Redding S Dies


These two videos explain most of the story

You will notice that the bushing FL sizing die without the bushing does nothing to the neck
You can also have the neck custom honed / probably a form die as well

This

Redding S die set PRICE

Explains the rest  for us in SA = PRICE ( and this is only for a TWO die set - NOT the three die set )

You will notice that most of these "serious dudes"  do de-capping as a separate process ...

[janfred]

Powder is Varget, N140, S335, S355. Some may use other, but then they must be too shy to talk about it.

Barrels are Krieger, Brux, Border, Lothar Walther to name a few. 30-32" long and cut with a custom chamber reamer.

Actions are mostly Barnard-P with a few Millenium and an Inch action or two. RSA actions are also used but are becoming fewer every year.

Thanks
So .. no SOMCHEM and no RSA barrels
The RSA actions were the Musgrave on the single shot competition rifle ?

Last time I looked, S335 and S355 is made by Somchem...