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I suggest you first neck the brass up straight,then use a Full Length sizing die adjusted long at first, successively lower to neck the cases back down to proper length to get what is called a 'crush' fit - ie; tight fit when closing the bolt. This will ensure the brass fits perfectly before a shot is fired. The reason for doing this is to ensure your brass lasts almost indefinitely.

The reason for I do this, is so the brass never stretches at the web, as it will if there is even a bit of headspace slop.

9.3x57 data will give you a very good place to start. If you go to www.gunboards.com then to the Swedish Military and Civilian Ctg. forum, you'll find a sticky thread at the top entitled 9.3x57 loads. There is a lot of data in there that will get you started on just about any powder easily available to you.

This case uses medium burning powders the best, in ball/spherical or stick - ie: H335, BLC2, H4895, Varget, the ADI equivalents of the H's, IMR4064, IMR4320, IMR3031.

These pictures how the one-step opening up of the neck on 8x57 RP brass, then sizing down to get a proper fit. Note the properly sized and 'fitted case' has a shoulder height that is .019" higher than a simply necked up case. To fire a simply necked up case in this rifle, would have stretched the case badly at the web, and it would have failed/split into 2 pieces in 2 to 4 firings. The .019" headspace of this rifle is excessive, but totally safe with properly fitted ammo.

The case on the left is a brand new 8x57RP case. The next one is a factory 8x57 case necked up to take a 366" bullet.
The third case is the 8x57 case necked straight in one pass with Imperial die wax or STOS used as an inside neck lube. the 4th case is one necked to properly fit the chamber of my rifle - a light, crush fit. Note the length of the neck compared to the 2nd case. It is .019" shorter and is easily seen. This rifle has excessive headspace and requires this type of case prep be done. Since I modified the .44 mag expander plug for this job, I initially form all my 9.3x62, 9.3x57, and .375/06IMp brass this way when making brass. After this step is done once, it does not need to be done again - after the initial fireforming, I neck size or partically FL size only. I never have to touch the shoulder again - no bumping, no FL sizing, brass is always an easy fit.

Edited by CptCurl (23/06/11 10:17 PM)

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