9.3x57 Brass Forming

[Uncle Grinch]

I just picked up a Husqvarna M38 Sporter in 9.3x57. It has a new barrel and a REM 700 bolt handle. Dies are on order and I’m looking for a mould. A buddy is sending me a few of his cast boolits to try. Brass is another issue. It appears Norma is the only manufacturer of this brass. I’ve got plenty of 7.92x57 new brass and I’m thinking I can reform it into 9.3x57 with my Hornady sizing die. Any tips or techniques will be appreciated.

 

[CWLONGSHOT]

I would think a trip thru the new sizer die, would provide serviceable brass...

 

[Spindrift]

A thing to consider:

When forming brass by necking down from a larger caliber, we can control headspace with the sizing die.

When forming brass by necking up from a smaller caliber, we're stuck with the original shoulder position. Which might work just fine, but potentially might lead to excessive head space.

When forming .35 Whelen from 30-06 pick-ups, I now start with necking up to .375, before sizing in a correctly adjusted Whelen FL die. This has improved my case forming process.

A versatile and cheap expander die can be assembled by combining the Lee universal decapping die, equipped with the relevant "Easy-x" expander, which is available as a replacement part.

Expanding your 8x57 to .375x57, before finalizing the brass in a well adjusted 9,3x57 die will ensure perfect headspace from the get-go.

 

[RBHarter]

You could just run some 06' in the sizer , anneal , and COW form it then trim to the actual case mouth .
This sets correct HS , true case length , and gives a glimpse of the throat .

Of course I neck 8×57 to form 7.7×58 that needs a .318 so what what do I know .

 

[Joshua]

I’ve done 30-06 to 8x57mm and 30-06 to 7.7x58mm. The pro about forming this way is that you are creating a new shoulder(safe headspacing), the con is you will have so much brass to trim.

While I haven’t done this, I have read that when necking up as you propose to do with your 7.92x57mm brass that simply seating your cast bullets so they heavily engrave into the rifling, and using a decent cast load of shotgun/pistol powder is all you need to do to get an “enough” first fire form. This can be followed up with a second reloading with jacketed at full pressure/stout cast load.

 

[Uncle Grinch]

Can you fire form 8x57 in the 9.3x57 chamber to “create” 9.3x57 brass?

 

[Joshua]

Can you fire form 8x57 in the 9.3x57 chamber to “create” 9.3x57 brass?

I edited my first post so that it was clearer.
I googled “8x57mm necked up to 9.3x57mm” many folks have done just that.
Assuming that your sporterized M38 rifle still uses a controlled feed extractor, and that you seat your cast bullets so that they engage the rifling your cases should fire form just fine.

 

[Ian]

When forming .35 Whelen from 30-06 pick-ups, I now start with necking up to .375, before sizing in a correctly adjusted Whelen FL die. This has improved my case forming process.

This creates a "false shoulder" or "false datum", excellent technique.l

 

[todd]

i've done them both, '06 case to 9.3x57 and 8x57 case to 9.3x57. the 8x57 comes up a little short on the length, but it is ok. the '06 brass needs a lot of trimming and possibly neck reaming.

9.3x57 (8x57 fire formed) with 275gr WFN GC at 100 yards

 

[Uncle Grinch]

Looks like you’ve got it dialed in Todd!

 

[todd]

thanks!!!

i gave the m46 to my gunsmith, who D&T , put on a scope mounts and rings, bent the bolt and a 2-position safety. it has a 2-7X Leopold on. i bought the m46 from Simpsons. i have killed three deer with it (30-50 yards) and they are DRT.

m46 and 280gr RN GC.

 

[fiver]

it's umm easier if you fire-form the 8 mauser brass first then do the conversion.
jus sayin i know a guy who will perform that service for you for a very, very low fee,,, you know like shippING [?shrug]