Location of 256 Winchester Magnum SAAMI drawings

[ohland]

CARTRIDGE & CHAMBER DRAWINGS INACTIVE CENTERFIRE PISTOL & REVOLVE

http://www.saami.org/PubResources/CC_Drawings/C%20and%20C%20Dwgs%20-%20TOC%20-%20Pistol%20-%20Inactive.pdf

Sorry, the links don't work in anything BUT IE....

Oops, maybe it doesn't work at all...

[EDG]

I think that is just a table of contents.
The drawings are in a much larger PDF.

Try this

http://saami.org/specifications_and_information/publications/download/206.pdf

[ohland]

I think that is just a table of contents.
The drawings are in a much larger PDF. Try this
http://saami.org/specifications_and_information/publications/download/206.pdf

Yes, you are right, that is a TOC, and it was SUPPOSED to link to the big file that you have the link for. It doesn't...

Huh, the old man picked up some Jameson brass a few years back and it was very loose for boolits (maybe J as well). I need to mic some necks of the 357 to 256 brass, was the chamber cut to allow for sizing down 357 Mag brass?

The 256 Win Mag is on page 48, and the chamber shows the neck as .2870 at the neck-shoulder junction, and the case mouth as .286. .250 bore and .256 groove, which suggests about .258 as the rule of thumb size-to. Oddly, the necks of factory 6.8mm SPC is @ .009, so using that as an average wall thickness (doubled) that is .018 + .258 = .276, with a throat of .1147

112718

[EDG]

Most of the cases I mess with are about .011 to .0115 thick. They vary down to .007 for Starline .38-55 and WW .38-40.
The max thickness brass I have ran into is .014. My .357 brass measures .011.

[jhalcott]

I use .223/5.56 brass in my Contender .256 win mag. I just replaced the extractor and it works fine. I remember a story in one of the gun rags about the first run of dies NOT sizing small enough, can't remember which magazine it was though. One thing about .357 mag brass, IF it has the cannelure/ring it is questionable to reform to 256. The ring will be at the shoulder neck junction and MAY separate on firing. My barrel is quite accurate, capable of sub inch groups(5shot) at 100 yards ,7x scope and off bags. Some chambers are a bit tighter than others and may need neck turning with some brass makes.