forming brass

[shooterpunk2]

I have always wondered how you form brass of one caliber to another caliber, for instance the 300 RUM to the 338 EDGE, how is this done? also how do you neck down to a different caliber? Thanks guys!

 

[milanuk]

Here's a page that gives a couple of options... it's for smaller cartridges (6mm BR to Dasher or BR-X) but the same general concept applies.

Forming 6BR Improved Cases

HTH,

Monte

 

[shooterpunk2]

so no one knows how to do this?

 

[Winchester 69]

Monte hasn't realized that his link didn't take.

The complexity of the individual process varies according to how much change the brass must undergo. For changing caliber with the same parent case, necking down with the smaller sizing die generally does the trick, unless the diameter reduction is so much that an intermediate step is needed. Similarly, necking up is accomplished with an expander mandrel; those mandrels used when neck turning work well. A sizing die with a tapered expander button will also work. When the case body must be reformed, it may simply be a matter of fire-forming the new cartridge in the rifle's chamber; the Ackley Improved cartridges have this characteristic. For more complex cartridge modifications, each will have its own procedure, and die manufacturers will have case- forming dies to do the job.

Someone who shoots the 338 Edge can help you with the specifics for that modification.
.

 

[milanuk]

Ack. Try the link now

When I was forming 6.5-08 (aka .260 Rem) cases from Winchester .308 brass, I bought a cheap ($25?) RCBS 7mm-08 die to use as an intermediate step. Nowadays, an intermediate sized bushing in a Redding Type 'S' F/L die would do the trick as well.

The tapered expander plug is what I'm currently using to neck up 6mm BR dash to a .25 cal neck (and then sizing back down to .24 to form a false shoulder for fireforming).