RCBS resizing die ?

KQguy

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Dec 7, 2007
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Can you reduce the size of the expander portion of the resizing die?It seems to put alot of stress on the case neck when I pull the die out of the case mouth,wich is probably a bad thin when you are trying to keep everything concentric.I was just afraid if I shaved the expander down too far,it would be too hard to seat bullets.Any advice would be appreciated.
 
Are you having a problem with concentricity?

Instead of grinding it down try it with the expander button removed. Compare the neck diameter from one sized with the button and one without.

I'm a believer that you can produce good quality ammo with reasonably low run outs with standard dies.
 
Can you reduce the size of the expander portion of the resizing die?It seems to put alot of stress on the case neck when I pull the die out of the case mouth,wich is probably a bad thin when you are trying to keep everything concentric.I was just afraid if I shaved the expander down too far,it would be too hard to seat bullets.Any advice would be appreciated.

Your problem is not with the expander ball. It must stay caliber size if it is to be used. The real problem is in the neck sizing portion of the die itself. Regular dies squeeze the neck portion down to as much as one or two calibers smaller and then the expander ball brings it back to the right caliber. So it is a lot of extra movement that the brass goes through.

Do yourself a big favor and buy a Redding type s bushing die. WIth the bushings, you can dictate how much neck tension you have and the expander ball can be totally removed from the equation. Runouts of "zero" can be attained with these type of dies.
 
KQguy,
What you're describing is friction as you drag the expander button through the neck of your cases.This is normal.
I wouldn't touch the expander until you have tried this!
With a neck brush of the correct diameter,a little bit larger than bullet diameter,dip the brush in powdered GRAPHITE,remove any excess,and run it into each case before re-sizing.You will know when you need to add more graphite when the cases begin to drag on the expander again.
This method will give you better cocentricity because the expander won't drag heavier on one side more than the other,this is what the dragging is.
Thsi will also make your necks stretch less,when the expander drags one side of the neck,it pulls that brass with it,making it longer on one side only.You can visually check this.
MagnumManiac
gun)
 
Your problem is not with the expander ball. It must stay caliber size if it is to be used. The real problem is in the neck sizing portion of the die itself. Regular dies squeeze the neck portion down to as much as one or two calibers smaller and then the expander ball brings it back to the right caliber. So it is a lot of extra movement that the brass goes through.

Do yourself a big favor and buy a Redding type s bushing die. WIth the bushings, you can dictate how much neck tension you have and the expander ball can be totally removed from the equation. Runouts of "zero" can be attained with these type of dies.
This statement is simply not true!
'Regular dies' do not squeeze the neck portion down to as much as one or two calibres smaller!The die only sizes the neck .001"-.002" smaller than the expander,then the expander brings the neck back up to .001"-.0025"
smaller than bullet diameter.
MagnumManiac
gun)
 
This statement is simply not true!
'Regular dies' do not squeeze the neck portion down to as much as one or two calibres smaller!The die only sizes the neck .001"-.002" smaller than the expander,then the expander brings the neck back up to .001"-.0025"
smaller than bullet diameter.
MagnumManiac
gun)


Well this one's easy to test. Pull the expander ball out of any one of your dies and measure the OD of the neck after sizing if you don't believe me.

I have a 7mm mag die that will neck down brass to a 264 win mag! That's two calibers. But most only go down around one caliber.
 
Well this one's easy to test. Pull the expander ball out of any one of your dies and measure the OD of the neck after sizing if you don't believe me.

I have a 7mm mag die that will neck down brass to a 264 win mag! That's two calibers. But most only go down around one caliber.

What planet are you from?
I have just done exactly what you said,this is about number 2000,because I check every die set I buy to make sure I get the neck tension i'm after.
RCBS 300WM Neck die with expander installed,neck measures .331" exactly.Expander removed,neck measures .3295".
Expander ball diameter measures .306" exactly,what I polished it to.
You do the math!
MagnumManiac
gun)
 
Just out of comparison,I've just measured 338WM brass in an RCBS neck die.light bulb
Neck dia. with expander installed .360".Neck dia. with expander removed .3585".Expander ball dia. .3358".
I don't think you are measuring it correctly!
Are you using a vernier or a micrometer?
MagnumManiac
gun)
 
I went through all this too when I first started reloading. After a few calls to Hornady everything was cleared up.

The biggest cause of the expander ball being hard to pull through is because the die is making the neck too small.

There are two causes of it making the neck too small.

#1. the brass in the case neck is too thick, most likely the problem since the die is squeezing the neck from the outside, thicker brass makes the hole too small and then the expander hangs up and is almost impossible to pull through, or

#2 the hole in die is too small, thereby compressing the neck too much. Hornady suggested I could send the dies back and they would open upthe hole for me.

A simple test for this is to turn the case necks down some and then try sizing the necks. They will pull through much easier when the brass is a reasonable thickness. This also explains the inconsistency of how hard it is to pull the expander through case to case, as I am sure you notice they are not all unbearably hard to pull through the die.

One other cause is really hard brass. A test for this is to anneal some of the cases and then try again. They will also pull through much easier when the brass is soft.

I have since gotten rid of all my regular dies and bought Redding Type S bushing dies. They solve the problem of brass in the neck being to thick as you can compensate for that with a different size bushing.

This does not completely solve all the problems though. If your case necks are not all the same thickness you will still end up with inconsistent neck tension since the sizing occurs from the outside. There are two choices to solve this, either turn the necks of the cases a small amount to make them all reasonably the same thickness or leave the expander ball on the Redding Type S bushing die.

I too had this exact same problem when I first started reloading and found the Redding Type S bushing dies so much better than regular dies, that I will never buy a regular die again.

Once you size with no expand ball there is no going back, it is just so much easier.
 
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I went through all this too when I first started reloading. After a few calls to Hornady everything was cleared up.

The biggest cause of the expander ball being hard to pull through is because the die is making the neck too small.

There are two causes of it making the neck too small.

#1. the brass in the case neck is too thick, most likely the problem since the die is squeezing the neck from the outside, thicker brass makes the hole too small and then the expander hangs up and is almost impossible to pull through, or

#2 the hole in die is too small, thereby compressing the neck too much. Hornady suggested I could send the dies back and they would open upthe hole for me.

A simple test for this is to turn the case necks down some and then try sizing the necks. They will pull through much easier when the brass is a reasonable thickness. This also explains the inconsistency of how hard it is to pull the expander through case to case, as I am sure you notice they are not all unbearably hard to pull through the die.

One other cause is really hard brass. A test for this is to anneal some of the cases and then try again. They will also pull through much easier when the brass is soft.

I have since gotten rid of all my regular dies and bought Redding Type S bushing dies. They solve the problem of brass in the neck being to thick as you can compensate for that with a different size bushing.

This does not completely solve all the problems though. If your case necks are not all the same thickness you will still end up with inconsistent neck tension since the sizing occurs from the outside. There are two choices to solve this, either turn the necks of the cases a small amount to make them all reasonably the same thickness or leave the expander ball on the Redding Type S bushing die.

I too had this exact same problem when I first started reloading and found the Redding Type S bushing dies so much better than regular dies, that I will never buy a regular die again.

Once you size with no expand ball there is no going back, it is just so much easier.



Thank you Doug. You are spot on but apparently, we are from another planet because we have had the same results.
 
What planet are you from?
I have just done exactly what you said,this is about number 2000,because I check every die set I buy to make sure I get the neck tension i'm after.
RCBS 300WM Neck die with expander installed,neck measures .331" exactly.Expander removed,neck measures .3295".
Expander ball diameter measures .306" exactly,what I polished it to.
You do the math!
MagnumManiac
gun)

Well, last time I checked, I called Earth home but I'm glad another newbie was brave enough to come on here and act like this site was 24 hour campfire or something and let me know I'm seriously displaced from home.

A bit of advice for you mr maniac, this site has respectable people on it who come here to get away from sites like accurate reloader and 24 hour campfire. There is no need to try and start fights. ANd if you DO try and start fights, it might help you to find out who you are fighting with before you fire the first shot and make sure you have some ammo to fire with.

You measured two dies that happened to be ok. However, you must know that brass neck thickness will determine your neck tension in any die. Therefore, you either have thin brass, a good pair of dies, or both. Die manufacturers know that every brand and lot of brass has different dimensions and therefore must design their dies to handle it all. The only way to do this is make the neck sizing portion very undersized for the caliber. This ensures that everyones brass will be sized. Your 338 mag die will absolutely size your brass to a different dimension than it will my brass. And my 338 die will probably not even touch your brass from the dimensions you gave me and it would be worthless to you. Like I said, I have dies that squeeze down the necks so far that I HAVE TO neck turn to use them or the concentricity is horrid. But if I turn them down too far, then they won't size at all.

THis is the whole reason that bushing dies were invented and I was merely trying to explain this to the thread starter. ANd I do know how to work a caliper by the way. I use two every day!
 
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thanks for all the help guy's,I decided to just buy a new Redding "S" resizing die.I just bought their competition bullet seater and love it.I think the redding resizing die is a good tool because you can use different size bushings,wich gives you alot of flexibility.
KQguy
 
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