204 to 6x47 ?

[camel]

Originally Posted by BangPop

I wonder if our president used to be a roo shooter.

Nah mate, our roo shooters aren't quite as brain dead as that.

[camel]

Originally Posted by Chuck Miller

Hmm...curious as to how that will work out. I've used 204 Winnie brass to make 222Mag but usually start losing some after the 2nd loading, necks split. I've always used std factory 222mag brass for my 6-47 with no issues. Jumping a 204 up to a 243 diameter I've never tried.

Ok thanks Chuck, I will find out how it works if he doesn't get any 222mag brass, and let you know. Did you anneal them after forming ?

[Tilleyman]

Have a Tikka M55 in 6x47mm (rebarrelled from 17 Rem) and tried necking up some of a mixed headstamp bag full of once fired Sako 222 Rem Mag brass I got with a Sako L461 in that calibre.

Found huge pressure differences with the Sako brass, but not with Remington .

On further investigation (incl sectioning a number of cases) I discovered some Sako brass had a strange 'lump' around the head near the flash hole, apparently formed during manufacture, that reduced the case volume.
I call this brass 'intermediate' and it needs to be culled from early and late headstamp brass or suffer the same pressure spikes I did...

I worked out which head stamps were affected... and did buy some NOS Sako but in the end had much better results with Remington 222 Rem Mag brass, heaps cheaper too

Definitely need to neck anneal after necking up but before firing as Remington cases seem harder in the neck...

[dungheap]

I never annealed any of the R-P or W-W cases I used in my 6x47, and never lost one to neck splitting, nor did I get the feeling I was (am?) brain dead as a result.

[camel]

Tillyman, that old Sako brass sure was thick, especially in the web area. good onya

[brians356]

Originally Posted by dungheap

Ka-ching!! Works like a charm, just run the .204's into my Redding die just like I would with .222 Mag brass. No difference in accuracy when fireforming cases either way. I used WW .204 brass, but I think any kind would work just fine.

That's good news. Ken Howell wrote in his encyclopaedic "Designing and Forming Custom Cartridges For Rifles and Handguns" that there was no practical way to form 222 Rem Mag from any other case. But that was published before 204 Ruger was introduced.