Minimum Saami for .308 win

[gsg5pk]

Do anyone have a number of Minimum Saami for .308 win?


I'm looking about different in case base diameter of each .308 reamer.

Seem like they are little vary on base diamerter .4722 , .4703 , .4700

So, just want to know the minimum saami of them.

 

[gsg5pk]

;D

 

[Rustystud]

Virgin Lapua 308 brass comes about .4665" in the web (.200" line). Most small base .308 chambers are .468" at the web. I see chambers cut in customers guns with webs from .468-.473". In my opinion no matter what web you end up with using the important thing is matching the resize die to the chamber. Brass is very ductile. The worst thing you can do is exercise your brass. That is expanding it during firing in a loose chamber and compressing it back in a tight die. The firing forming of the brass is "explosion forming (with heat)" and the resizing is with a "cold forming in a die". Much less destructive to the brass when adding heat to the process.

The differences in case volume with the variances web diameter are negligible. I personally like a .468" web so it keeps the case in its original taper.

Hope this helpful.
Nat Lambeth

 

[gsg5pk]

Nat,
Incase that my chamber was cut with reamer spec .470 base. What sizing die web diameter recommend?

What is the web diameter of this die
Redding small base fl sizing die
Redding standard base full length sizing die

 

[Rustystud]

You can't necessarily go by the reamer spec alone. Depends on the chamber run out. I would fire a case measure the web of the fired case. get a die that is .002 smaller than the expanded web. This will resize the case and it will have about .001" spring back. It will minimally size the case and allow for re-chambering the reloaded cartridge.

When someone builds a new rifle or re-barrels a rifle, I always recommend they start off with new brass. If they don't they are often asking for a rash of problems. If a chamber is tight in the web area most smiths will polish the web until they get the cases to fit. Often this takes a lot of polishing and is counter productive.
Nat Lambeth

 

[gsg5pk]

You can't necessarily go by the reamer spec alone. Depends on the chamber run out. I would fire a case measure the web of the fired case. get a die that is .002 smaller than the expanded web. This will resize the case and it will have about .001" spring back. It will minimally size the case and allow for re-chambering the reloaded cartridge.

When someone builds a new rifle or re-barrels a rifle, I always recommend they start off with new brass. If they don't they are often asking for a rash of problems. If a chamber is tight in the web area most smiths will polish the web until they get the cases to fit. Often this takes a lot of polishing and is counter productive.
Nat Lambeth

I found that Whidden FL Sizer Die mention their die spec was minimum Saami.

So What about this one.

 

[Ggmac]

Get a lee carbide 45acp die , gut it cut the top off and run your brass thru this first . If using used brass . The Lee carb is .467 , you still nee to full length after the carbide .

 

[gsg5pk]

Hi Nat,



My fired Lapua brass measure .468" - .469" at web.