Options for expanding necks on 8x57 to make 9.3x57?

Suther

Suther

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Just bought a 9.3x57 Husky rifle. 9.3x57 brass is pretty darn expensive, so I am planning on using 8mm Mauser brass (probably PRVI brass, haven't picked anything up yet though). I am aware that the Hornady 9.3x57 dies are designed to be able to neck up 8mm brass, but I've also read that the best option is to neck them up to ~40cal, then size them down to 9.3 because doing it this way you can create a false shoulder which allows you to set the headspace to your specific chamber.

I don't have anything in my reloading setup bigger than 30cal currently, so I don't have anything on the shelf that'll expand the case mouths. With that in mind, what is the cheapest, easiest, and best ways to accomplish my goal?
 
IMHO.
Anneal the brass first.
Just load 10-12gr of non-magnum pistol powder. W231 titegroup, HP38 etc.
Corn meal to just under case neck and melt candle into case mouth.
Fire in your chamber at the range. and enjoy the cloud.
Clean brass , de-prime and resize.

Can't say I see any great advantage to opening it out to .40
 
The advantage to first opening it up to 40 is that you can then size the brass to fit the chamber in the rifle perfectly.

Adjust the sizing die to form the neck a bit at a time on one case until the bolt will just barely close on that sized case.

Lock the die in place and resize all the brass.

You now have perfectly-sized cases for that particular rifle. Case life will be significantly increased in rifles that have excessive headspace.

The sized brass can be reloaded with full charges, no fireforming needed, and used for target shooting or hunting.

I use an RCBS 30-40 neck expander die.

iK5G7Xzl.jpg


Some guys on here use a LEE 40 cal pistol die to expand the neck

Ted
 
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Okay cool. Any idea where I can pick up one of those fancy looking expander dies?

When you say some use Lee 40cal dies, I assume you mean one of the dies sold with the normal 40 S&W/10mm die sets?
 
Don't know if they still have it but I bought some once fired Norma brass from Anthony at Tradeex. It was more affordable than new at that time, a few years back.
 
Cheap and easy without buying anything extra to expand the necks you could aneal the necks and run them through the 9.3 die, jam a bullet into the lands for the first firing to fireform to your chamber with a lighter load.

I find necking up easier if I use imperial sizing wax inside the necks, run them up and flare the neck a bit till I start getting significant resistance then pull the ram down apply more lube to the inside of the flared neck then go the rest of the way, less chance of buckling at the shoulder that way, after the second application of lube they will go over the expander ball with alot less resistance.

I haven't any experience with 8x57 to 9.3x57 but that method has worked well for me going 7mm& 30 cal to 35 cal expanding necks & fireforming to my chamber.
 
Ive been using the 9.3 hornady die set running my 8x57 brass straight thru and using as is. Haven't had any issues yet and accuracy is still great with irons. 2 inch groups at 100 yards!
 
dgradinaru said:
Ive been using the 9.3 hornady die set running my 8x57 brass straight thru and using as is. Haven't had any issues yet and accuracy is still great with irons. 2 inch groups at 100 yards!
Click to expand...

Good to hear. I am thinking I will likely just try that first, but I want to make sure I have the process and tools all figured out in case I realize I have a long chamber or something.
 
Why not? said:
The advantage to first opening it up to 40 is that you can then size the brass to fit the chamber in the rifle perfectly.

Adjust the sizing die to form the neck a bit at a time on one case until the bolt will just barely close on that sized case.

Lock the die in place and resize all the brass.

You now have perfectly-sized cases for that particular rifle. Case life will be significantly increased in rifles that have excessive headspace.

The sized brass can be reloaded with full charges, no fireforming needed, and used for target shooting or hunting.

I use an RCBS 30-40 neck expander die.

iK5G7Xzl.jpg


Some guys on here use a LEE 40 cal pistol die to expand the neck

Ted
Click to expand...

glad you find one back.
 
I got a 3-pack of expander/decapper (.416) on ebay. Fairly cheap and no problem getting them up here. They have a long taper so it works well for expanding the necks.
 
All I've done is resize the 8mm brass using a Hornady 9.3x57 FL sizing die. I've done several hundred and haven't lost a case yet. I read that the Hornady sizing die has a more gradual taper on the expander button and is supposed to be easier on the brass than other dies but I don't know that for a fact.
 
Any tapered expander will work. I have done hundreds and hundreds of 30-06 to 35 Whelen, 308 to 358 Win, 338 Win Mag to 358 Norma and 300 WSM to 35 Sambar. If the brass has been fired I will anneal and if new I don’t. If I anneal I virtually get no lost cases. I use Hornady One Shot spray lube and either RCBS OR Redding dies but Lee work too. I load to mid pressure as with these first case firings I’m not doing accuracy work but I’ve honestly found them to be just as accurate. With calibers that are simply necked up and nothing else, don’t overthink. Neck it up, load it, shot it and there is your brass for good.
 
Lee make a universal case expanding die set with two tapered expanders that will cover just about every cartridge imaginable. Bought mine from Budget Shooter Supply , very reasonable in price and works great.
 
A tapered ball on the decapping stem is easy. Some standard ones work well enough anyway, which would give you free and easy. Some of the stems are pretty light and you might be stressing it more than you want though. They are made for pulling, not pushing after all. If you're the sort of guy that likes to check run-out the results might make you hide under the bed and shiver. ;)

Expander mandrels from Sinclair and others work well, but aren't real cheap. Not expander ball cheap anyway.

The COW method will work, at the price of a small charge of powder, a primer and some dicking around. I save that for major shape changes like making .458 Lotts out of .375 H&H. Doubles as a short range shotgun for grasshoppers.

An old but somewhat novel way is to seat a 9.3mm bullet upside-down in a chamferred 8mm case and then pull it again. You can use the same bullet over and over, and if you used it for a fouler I suppose you could call that free, if you don't mind screwing dies in and out.

An effective redneck method is to find a 9.3mm bullet with a boat-tail and just seat it into a charged 8mm case and shoot normally. Don't laugh; there will probably be less run-out than the above methods. I do it all the time to make .338 Edges out of .300 RUM brass, and shoot them at 1/2 mile.
 
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