Forming 8x57 from .30-06?

[jason280]

I recently picked up a Mauser K98, and finding 8x57 brass has become a bit of a challenge. Fortunately, I have several thousand cases of 1x fired .30-06 brass...and looks like it *might* be somewhat straightforward to resize to 8x57 Mauser.

Any tips or suggestions from those who've done this?

[tdoor4570]

Pull the expander out of the 8x57 die , lube 06 brass run through die, trim to length run back through die with expander installed, light load with cast slug and fire form, anneal and load. I have done 100's for my 3 8x57 mausers

[pworley1]

It is a very simple operation. A 8x57 file trim die makes it really simple. If you don't have the trim die you should trim the brass to approximate length and run them into the 8x57 size die. Trim to final length. Depending on the brass, you will probably need to turn the necks. If you have the trim die you can just run them into it and trim with a fine toothed saw. You will still most likely need to thin the necks. Good luck.

[Hick]

Whether or not you need to turn the necks may depend on your firearm. I have a 1909 Argentine Mauser in 7.65 and also make my brass from 30-06. After cutting to length and sizing the brass is definitely thicker at the mouth-- but it fits the '09 Mauser chamber nicely even when expanded for a boolit. My recommendation would be to try it without turning the necks and see how it does.

[jason280]

Ideally, I would like to use 1x fired LC '06 brass, but I don't like the idea of having to *potentially* turn necks.

[racepres]

Ideally, I would like to use 1x fired LC '06 brass, but I don't like the idea of having to *potentially* turn necks.

Havent turned a neck yet for Misurps... and, I run thru the 8x 57 (no Expander) die, then cut off excess length with a tubing cutter... Deburr aggressively, then run thru sizer with Expander in.. a quick zip with my Lee cutter and lock stud, with the Shellholder that can be chucked in cordless drill.. Shoot away... long as a Projectile will pass into a fired neck...No Need to Turn... and, I havent yet!!!

[GrizzLeeBear]

I don't have any 8mm Mausers anymore, but I have had several in the past. I formed hundreds of LC 06 brass into 8x57 and never had to turn any necks. Most Mausers have generous throats so don't need any neck thinning. I highly recommend the Redding form & trim die over the RCBS.
See my post #17 in this thread on the subject for how I used to form them.
https://castboolits.gunloads.com/sho...sing-a-Lee-die

[jason280]

Thanks!

[ascast]

I done a bunch as described above. necks for .308 bullets don't get thicker when blown out to .323. You might get a neck split or two as a thin spot stretches. good luck

[15meter]

I chose to use 270 Winchester brass as the donor case for the simple reason I don't own a 270 and there are 5 06's in the safe. I have formed a few from '06 but much prefer the 270.

With you having a pile of '06, I most certainly would use them.

A couple of things, anneal AFTER the forming and trimming. Don't do any neck turning/reaming until you measure. My Turkish Mauser did not need any.

Do small batches at a time (5-10 pieces) until you get your procedure down pat. It's frustrating thinking you have the process under control, then having to redo or scrap out a hundred or two because they're just not quite right.

If after full length sizing and trimming, it takes too much effort to chamber, grind .005" off the top of the shell holder, reset the die and size again. You may get some spring back and not get the shoulder pushed back far enough to chamber. If it still doesn't chamber try taking another .005" off and trying again. Keep going until you get it to chamber.


Good luck, and don't forget to anneal before shooting, you'll get much longer case life.

[TurnipEaterDown]

I have reformed a number of different 30-06 cases for my Yugo 8x57 cast bullet practice gun.
I agree w/ several prior posts, the exact steps can vary, and what I do is trim 30-06 brass to 8x57 max length, run into my 8x57 die (lubed inside neck and outside normally), resize, check for neck thickening, turn if required, trim to length.

I also just chamfer generously and avoid the cast bullet expander dies (M die type). I get away with it, using a GC bullet at 0.325", no shaving.

I do check the necks carefully, as lots of brass from different makers differ in construction, and what you get after reforming will vary.
I have reformed Fiochi, nny, ppu, Military (LC & HXP), etc. Some are great w/ uniform necks after forming, some get pretty thick about 1/3 or the way down from mouth. Some can also make a ring inside. I just avoid those.

Like said before, measure the thickness of the formed neck, and if uniform and will expand far enough to pass a bullet freely when fired, you can use as is. Just measure a fired proper 8x57 case, the neck thickness and ID, the neck thickness of your reformed brass, and do some math.

If the neck isn't uniform over the whole length, I turn to get uniform tension.

Also, if the necks get too thick, you can have trouble on the downstroke out of the resizing die. The body of a standard resizing die will pull the neck down for a standard thickness neck, and if too thick the small resultant ID will tend to create much more force to pull over the expander. I don't like to lube the interior of necks after forming (like I have had to do w/ thick necks left unturned), and never have to w/ factory brass.

I think the surplus 8x57s make a great practice gun for offhand, working the bolt from shoulder, quick target aquisition & firing, etc.
Mine are beaters, I clean very infrequently, are pitted as heck in the bore (were when I got them, I didn't make worse), and still give me 20 shots into ~ 2.5" and 40 into ~3-3.5" w/ cast bullets at 100 yd. I usually clean them when the bolt rotation gets gummy, or it has been a couple seasons (summer-fall, winter spring, etc). I do have a borescope, and find w/ a good lube and proper bullet mine will clean easily even after 400-500 rounds.
The brass seems to last a long time w/ cast bullets at ~ 1600 fps. In the first couple years of having mine I used up 2 boxes of gas checks and still hadn't had all of my first 50 pieces of RP factory brass fail. (I was admittedly replacing as they failed, so something less than 40 shots on a case). That's some good life when I don't bother annealing! Maybe I just got lucky w/ my set of LEE dies and the chambers in the guns I got, but I don't usually get too lucky too many times in a row.

[Hanzy4200]

I do this without any fuss or fiddling. Get a $10 Harbor Freight hop saw. Saw them off at roughly the right point (you'll find the sweet spot). Deburr them well, lube with Imperial Sizing wax, resize in the 8MM die, then trim to exact length. No annealing. That simple. I use this method for 7.7 Jap and 8MM, and I've never had a split case. I prefer to use .270 Win as I make use of the 30-06 in it's original form.

Not annealing is just my preference. Many would argue different.

[armoredman]

@LAGS He made a bunch for the 8mm Mauser I have some time ago.

[Geezer in NH]

I have made hundreds with my form/trim die. I think it is a Redding die I got years ago from Midway. I full length size after then load after annealing the mouths and necks.

[wmitty]

Using .270 brass enables sizing in an 8 x57 fl die and chambering the sized brass to check headspace. I realize primers are hard to come by right now, but blowing the neck forward with a pistol powder and cornmeal or dry rice allows seeing where lands begin and an idea of throat diameter. I guess you can cut to correct length and open the neck with a tapered expanding pin, I just have not tried it that way. I was fortunate enough to have bought some large rifle primers before the last spontaneous disassembly occurred.

[WardT]

Using Mil 30-06, I annealed before forming.

[MostlyLeverGuns]

Easier to trim before sizing, have NOT had any issues with need to neck turn in 3 98 Mauser 8mm's. Trim, lube case neck inside along with usual exterior. Set your sizing die so shoulder is set properly for chamber. Annealing helps make things easier and does extend case life, but not absolutely necessary. In the 60's, genuine Army surplus stores had 30-06 brass in 55 gallon drums for 6 cents a pound, as a kid without deep pockets, I made any brass that would work from it, mostly 8x57 and 300 Savage, no neck turning, but it worked.

[kungfustyle]

These help
https://www.ebay.com/itm/15435324387...3ABFBMtsOgh4dg
https://www.harborfreight.com/2-in-m...saw-62136.html
form and trim die from RCBS and you can crank these out in no time.
I used a hack saw and the form and trim die but the Harbor Freight mini saw is a massive time saver.
Annel the brass, trim, form and trim die, champfer/debur then run it through the 8mm size die.

[mdatlanta]

It’s interesting that some folks say to anneal before forming, some say to anneal after forming, and some say no need to anneal at all. Just proves there’s more than one way to skin a cat! ��

[mikeinnm]

Might be prudent to mark somehow if the headstamp says "30-06", and there's a chance of someone besides you using the finished ammo: 8x57 can chamber in a 30-06, but if it's fired in an '06, it could make for a Very Bad Day.