Case Neck Expanding.

cjs66

Well-Known Member
I've got a few neck expanding mandrels and the associating die that I use on new brass to straighten the necks out. I've a question for those that use these in their normal brass prep. Do you take the Spindle with the expander ball out of the FLS/NS die, size as normal and then use the mandrel to size the neck? Using the mandrel feels much smoother than dragging the sizer ball through.

Ta.

cjs
 
It is… I never really liked the idea of dragging the sizer back through the necks, seems counterintuitive to me. 🤔

You could just take the expander off the spindle, I use the Redding S Type bushing dies without the expander to get where I want to be on neck tension and then just run the cases through an appropriate mandrel.

Cheers,

Fizz
 
On most of the calibers I reload, before F/L I smear some Imperial Sizing wax on a soft brush and coat the inside of the case neck, this makes it a smooth process bringing the expander through the case. After that I use a Wilson Expander die to (as much as possible) uniform the necks. Obviously when using S type dies I don't use the Wilson Expander.
 
Yes, I pull the expander ball assembly form the FL die, then use the mandrel expander die in a separate step. This goes for manually loaded brass, as well as brass done on automated machinery.
 
I've got a few neck expanding mandrels and the associating die that I use on new brass to straighten the necks out. I've a question for those that use these in their normal brass prep. Do you take the Spindle with the expander ball out of the FLS/NS die, size as normal and then use the mandrel to size the neck? Using the mandrel feels much smoother than dragging the sizer ball through.

Ta.

cjs
Yep remove the spindle from the full length sizing die , size the case then as suggested move to the next stage with the expander die body and appropriate expander mandrel .
I use case lube on the body of the case and inside the neck for a really smooth operation knowing the correct neck tension has been achieved on both operations.
Colin
 
Just for clarification as I was literally just discussing this with @Malxwal last night - do you mean in my Hornady dies I should remove the section in red or the whole stem, and buy a separate die for doing the expanding?

Is doing it sperately to ensure it’s properly lubed or something?

I usually lube the outside of the case and put a small wipe of lube on the ID of the neck before running it through the die (I use Hornady sizing wax)

IMG_5032.webp
 
Just the bit you highlighted in red - if it's removable.
I don't tumble my brass after sizing, so I wax the case body, then just dip the neck into dry lube (graphite) media a few times and resize. After sizing I use an expander mandrel then I wipe the case with a bit of kitchen tissue. I don't wipe out the inside of the neck as the graphite makes seating the bullet smoother.
 
Just the bit you highlighted in red - if it's removable.
I don't tumble my brass after sizing, so I wax the case body, then just dip the neck into dry lube (graphite) media a few times and resize. After sizing and expanding I wipe the case with a bit of kitchen tissue. I don't wipe out the inside of the neck as the graphite makes seating the bullet smoother.
So what do you use for the expanding part? A different die specifically for expanding?
 
So what do you use for the expanding part? A different due specifically for expanding?
I've edited my previous reply, but yes. I use a Sinclair Expander die which has removable mandrels. So you buy 1 die then buy the mandrels in the calibre and inside neck diameter to fit your rifle calibres. See link below:
 
1967 Spud. Cap screws off to change Mandrels.
Ken.
Ps. I set the neck tension at 0.002.
 

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Just for clarification as I was literally just discussing this with @Malxwal last night - do you mean in my Hornady dies I should remove the section in red or the whole stem, and buy a separate die for doing the expanding?

Is doing it sperately to ensure it’s properly lubed or something?

I usually lube the outside of the case and put a small wipe of lube on the ID of the neck before running it through the die (I use Hornady sizing wax)

View attachment 355731
Not familiar with Hornady dies but if the whole assembly comes out, remove the whole lot. Bare minimum get rid of the bit that sizes the neck back up when it's drawn back out the case on the up stroke of the press handle.

The overall feeling of drawing an expander ball back out of case feels like too much stress on the brass to me. It is really pulling it and it feels graunchy. I used to wonder if it was almost stretching the neck/shoulder, such was the force required even when properly lubricated.

The nice thing about using an expander mandrel die, is that you effectively turn your FL die in to a basic body bump die where you just using its internals to size the overall case body and shoulder while also sizing the neck down as would happen when the expander ball assembly was in the die. When you then use the expander mandrel die afterwards, you are sizing the neck back up when you drive the mandrel in to the case rather than on the way out and the force required to do that feels much less. It is also easier to do on the downstroke of the press handle. You can also just dip the case in to dry lube (I use graphite) sparingly which means no need to clean afterwards. And it is much easier to dip in to a graphite than to internally lube every case neck internal.

Neck tension seems much more consistent to me this way. It is hardly a scientific conclusion but you can tell a huge amount when seating bullets. When they all slip in the same like butter, you know you are getting consistent neck tension across the board and the numbers on the chrono back this up, in my case anyway. Others milage may differ but I am a big fan of case bumping without expander ball in the FL die and then using a separate die/mandrel to size the neck.
 
I push a case neck into this sizing wax a twist it back and forth two or three times, then put it through the sizing die, (Sometimes just a neck die, other times a FL die) I follow this with another 4 cases through the die before waxing another case neck.
When all cases are sized I expand them with the mandrel, no more lube needed on any case.
Ken.
 

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Yep remove the spindle from the full length sizing die , size the case then as suggested move to the next stage with the expander die body and appropriate expander mandrel .
I use case lube on the body of the case and inside the neck for a really smooth operation knowing the correct neck tension has been achieved on both operations.
Colin
Just for clarification on the removal of the spindle ect
 

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I'm missing something here.
I just size in one go and load.

You guys bench rest shooters right?
Hi
Remove the spindle as shown .
Size just the body of your case in the empty fl die , then put the case into a separate expander body with the appropriate size expander mandrel and size the neck of the case , this will give you consistent neck tension.
Yes I do benchrest and hunt
Regards
Colin
 
Hi
Remove the spindle as shown .
Size just the body of your case in the empty fl die , then put the case into a separate expander body with the appropriate size expander mandrel and size the neck of the case , this will give you consistent neck tension.
Yes I do benchrest and hunt
Regards
Colin
Mate of mine now departed did BR. He had all the kit.
I'm good over the distance I shoot.
Next you'll be getting a tight throat barrel and neck turning every case.
ATB
 
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