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Is this a donut and as such a problem?

I am reloading .308 and use Wilson dies (only neck forming).
I see now that the fired and formed cases show a bulb at the bottom of the neck.

see picture for clarification the left case is new and the case on the right is neck sized, there you see the bulb I mean:


Question: is this a problem? (the loaded case fits into the chamber)
Should I change things to prevent this?

thanks.
 

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I don't think so it looks to me that your die is not set low enough to size the neck lower. A donut would be on the inside and you would either have to cut your piece of brass in half to visually see it or take a piece of wire down thru the neck and feel for it. Try setting your die lower and that will neck size your brass more.That particular piece of brass shown does not look like it was neck turned yet?
 
not sure.... but i beleive the donut forms on the inside of the neck........looks like you don't have the press/dies set-up properly.
 
definitely not set up correctly or there is a problem with your die.
 
The neck is just not sized all the way down to the shoulder joint. Re-adjust the die, or grind a little off your shell holder.
 
Thats what mine looks like when I partial neck size. I wouldn't say the dies are setup wrong. The purpose of neck sizing is to make the brass fit the chamber as best possible. Leaving a portion of the neck unsized ensures that the case is perfectly centered in the chamber. When a donut forms you will feel a ring at the neck shoulder junction. This can be felt on fired cases by sliding a bullet down into the case This is mostly caused by seating the bullet too far out of the case neck. When the case is fired brass flows into this area. As I understand the best way to avoid this it to have your chamber throated correctly?

Lance
 
Thank you!

Indeed using Wildon neck die you always partially size the neck (1/3 only) but with my other calibers (.300 WM, .270, .243, 22-250) I don't see this problem.
Could it be the room in my chamber is more than suppost to be and then partially neck sizing causes this?

I don't have a donut on the inside of the neck!

Big question remains: Is the bulb on the outside a problem? My thinking is: this bulb makes the case center perfectly into the chamber of my rifle because it is exactly the diamater of the inside of the chamber, it fits perfectly snug so to speak.
 
It's only a problem if you don't like it or if the the gun doesn't like it.
I shot a 6.5 284 the same way. It didn't hurt one bit. In fact, if I sized the whole neck, it shot worse. Even if I went to a bigger bushing (not that you have that option with your Wilson).
I noticed that this can be where a lot of run out can enter into the equation. It seems the more tension or surface area involved can lead to more run out error, at least for me.
There was talk about a 2 part sizing die pertaining to this very thing.
I think German Salazar was thinking along those lines anyway. Makes sense to me.
You need something to size/hold the body centered till/while the neck gets sized.
I don't know, I feel like I'm just rambling now.
Jim
 
Robbert said:
Thank you!

Indeed using Wildon neck die you always partially size the neck (1/3 only) but with my other calibers (.300 WM, .270, .243, 22-250) I don't see this problem.
Could it be the room in my chamber is more than suppost to be and then partially neck sizing causes this?

I don't have a donut on the inside of the neck!

Big question remains: Is the bulb on the outside a problem? My thinking is: this bulb makes the case center perfectly into the chamber of my rifle because it is exactly the diamater of the inside of the chamber, it fits perfectly snug so to speak.

Well since you already know that the Wilson only sizes part of the neck and you have a bugle on the unsized part seems to me that is from your chamber and has nothing to do with the die. To elimate that you need to change type of die you are using might want to try a Redding type S die they normally size the entire neck.
 
Don't change a thing. This is not a donut, or a problem.

There is never a reason to size any more of the neck, as this provides plenty of tension. I use Wilson as well, and drop a bushing around the case head before sizing to provide one cal of sizing distance.
And my ES is incredibly low.
 
I think it looks that way 'cause you turned the necks, and now the neck needs too much sizing for a bushing.

What do the cases measure before and after sizing?

Jim
 
Jim, when he seats a bullet the neck should measure correct OD, there will be plenty of tension(if not too much), and the round will chamber fine -all else being right.

All of my brass(turned or not) looks just like his before seating.
And I've done this for a long time.
 
Refering to the interest of neck sizing only.
2 part die. One part to hold (not size anything) and one part to neck size.
zullo74 said:
holstil said:
You need something to size/hold the body centered till/while the neck gets sized.
Yes, that's just what a full length sizing die does!
 
thanks for sharing all your thoughts! It has been of great help drawing my own conclusions.

I did use Redding S type aswell as e reference for my self this full length die was set up to size the entire neck.

So my conclusion is don't worry, this is not a problem as long as nothing else suddenly changes.

regards, Robbert
 

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