Redding Competition Shellholders

[Bitis Arietans]

Good Day, All
I've pick up the Redding Competition Shell Holders Set. Loading for 7MM Rem Mag (Sako 85 Finnlight)
I'm trying to minimize should bump (to .002", or so) As I understand it the .010 holder (.010" deeper, than the standard shell holders, that are usually .0.125") will allow the case to travel into the Sizing die (Redding Type S) less, and reduce the shoulder bump.

The instructions with the new holders recommend that you start by using the deepest holder (.010"0 first; size the case and attempt to chamber the cartridge. If it wont chamber, or chambers with difficulty...use the .008 and so on.

Surprisingly, after sizing with the .010 holder the round still chambers! It's like I need a holder that's even deeper! I have set the die in the press so it touches the press's ram firmly (w/ a little cam-over)

I've tried contacting Redding, but sadly they are unavailable due to inventory work.
Thoughts...

Thanks much, as usual

 

[bigedp51]

A normal shell holder has a deck height of .125 and the plus .010 competition shell holder has a deck height of .135. Meaning the plus .010 competition shell holder pushes the case .010 less into the die.

All the competition shell holders are designed for "LESS" shoulder bump than a standard shell holder in .002 increments from +.002 to +.010

And if you need more shoulder bump you lap a standard shell holder. This decreases the distance from the deck of the shell holder to the bottom of the die.

Simply put using the competition shell holders is like putting a feeler gauge between the shell holder and die for less sizing. Meaning the +.010 shell holder is like placing a .010 feeler gauge on top of the shell holder and then adjusting the die down to contact the feeler gauge.

 

[gohring3006]

Are you saying your brass chambers easily even before you size it? How are you measuring shoulder bump?
How many firings on your brass prior to attempting the die set up?

 

[gohring3006]

http://www.longrangeonly.com/how-to-adjust-and-set-head-space-and-shoulder-bump/
This will help explain it better.

 

[Mikecr]

Is the brass fully fire formed yet?

 

[Bitis Arietans]

Is the brass fully fire formed yet?

Thanks All, for your replies!
The fired brass actually, DOES chamber with out sizing.
Yes, the brass is fully fire formed, in the same rifle...maybe fired once or twice. I thought of lapping the .010" shell holder, but I'm afraid it just wont sit "square" while contacting the press ram

 

[gohring3006]

If you brass is clambering without resistance, lapping the shell holder will make things worse. Your brass may not be fully fireformed to your chamber yet. I don't set my full length dies up for shoulder bump until after the third firing. I necksize until that point.

 

[Bitis Arietans]

If you brass is clambering without resistance, lapping the shell holder will make things worse. Your brass may not be fully fireformed to your chamber yet. I don't set my full length dies up for shoulder bump until after the third firing. I necksize until that point.

 

[Bitis Arietans]

Gohring....
Thanks much. That may indeed be the answer!! I didn't know that the cartridge case MAY require several firings, to be truly fire formed.

That has to be it!!

Would you recommend, NOT sizing the brass at all for my handloads until I reach the point that the fired brass does NOT chamber....and then start the process that Redding recommends starting w the .010 and so forth??

Thanks again

ba

 

[gohring3006]

Gohring....
Thanks much. That may indeed be the answer!! I didn't know that the cartridge case MAY require several firings, to be truly fire formed.

That has to be it!!

Would you recommend, NOT sizing the brass at all for my handloads until I reach the point that the fired brass does NOT chamber....and then start the process that Redding recommends starting w the .010 and so forth??

Thanks again

ba

I don't go until they don't chamber, but I do fire until I can feel a good bit of resistance when closing the bolt. It's obvious when it's time to set up the die.
I neck size only until that happens. You can set up a full length die to size just the neck, but it also stretches the case slightly and you don't really get a good feel when your brass is fireformed because they all get stiff when doing so.
It was easier for me to just use a lee collet die because I set up my die kit for all of my rifles using it and a Redding body die, with the exception of 338 Lapua.

 

[Mikecr]

In the beginning of this thread you said you wanted to minimize shoulder bump to ~.002". This is right, but what do you think that means? Why is this done?

Before doing ANYTHING in reloading, these questions should be applied.

 

[Bitis Arietans]

As I understand it reducing shoulder bump to a minimum will cause my brass to expand less, thus increasing the brass life... and may improve consistency

 

[Mikecr]

As I understand it reducing shoulder bump to a minimum will cause my brass to expand less, thus increasing the brass life... and may improve consistency

Good,, minimal from what?

 

[Bitis Arietans]

I think that the video sent by gohring explains it best. Start with a fully fire-formed case. (that won't chamber) Start with the .010 shell holder...and proceed till the round chambers
Is that correct? Am I missing something? Thanks for your help!!