Can you rechamber the 8X57 JS to 8X64 by doing nothing more than reaming the chamber in an existing rifle? Will the 8X64 cartridge work in a rifle originally chambered for the 8X57 (Oberndorf Mauser sporting rifle) without any magazine modifications?

Why not the 8mm-06 (8x63) AI? I believe it would almost match the 325wsm capt david

The 8mm-06 is probably difficult in France, with the ban on military cartridges and no legitimate brass.

The 8x64 technically is a tight fit in a standard 98 magazine. The OAL and the mag length are the same. The good news is that the factory cartridges I have seen were only loaded with bullets of 196 and 198 gr, which had a shorter OAL.

I am going to assume that this commercial Oberndorf has already been modified in some way, as you would be violating some unwritten law of ethics if you alter a pristine model.

Yes the 8X64 will clean out the 8X57 chamber nicely.

The other good news is that with nothing but a file, the standard M98 magazine can be lengthened to about 3.38"

Take the rear mag wall down as thin as possible, gaining about .050". Then take another .015" from the front. You may have to grind a bit off of the bolt stop to allow the bolt some additional rearward movement, but this is not always the case.

BTW The 8mm-06 Ackley Improved will not equal the 325WSM in case capacity or performance. It will come up about 100-150fps short of 325WSM factory laods for the 200gr bullet.

Wink,

if you're going to make a Mauser 8x57IS legal in France, the 8x60S is another, and IMHO better, option. It has the same prestanda as the 8x57IS, or just slightly faster. And you will have the great advantage of high quality modest priced factory brass from RWS. The 8x64 is only available cheap and worthless from Sellier & Bellot, or expensive, really expensive from Brenneke.

Regards,

Fritz

quote:

---

Originally posted by KurtC:

I am going to assume that this commercial Oberndorf has already been modified in some way, as you would be violating some unwritten law of ethics if you alter a pristine model.

---

Kurt, I'm still stuggling with the moral and ethical issues on this one. Yes, it is a pristine Oberndorf Mauser in original unmodified condition (made in the nineteen thirties) except for the claw mount scope (also mounted in the thirties). My problem is that it sits in a safe in the USA and I can't import it to France without going through a dissuasive and expensive process of obtaining a War Materiel Import License. The seperation between and my rifle is unbearable, what to do?

quote:

---

Originally posted by Wink:
Can you rechamber the 8X57 JS to 8X64 by doing nothing more than reaming the chamber in an existing rifle? Will the 8X64 cartridge work in a rifle originally chambered for the 8X57 (Oberndorf Mauser sporting rifle) without any magazine modifications?

---

Yes, as to rechambering. But to find out about feeding from the mag., just get three or four loaded rounds and see if the mag. will hold them and feed them, before you do any cutting!And, I see no problem with the 8X63 (8mm/'06) either, since it is NOT a military cartridge. No government has ever used it!!

quote:

---

Originally posted by Fritz Kraut:
Wink,

if you're going to make a Mauser 8x57IS legal in France, the 8x60S is another, and IMHO better, option. It has the same prestanda as the 8x57IS, or just slightly faster. And you will have the great advantage of high quality modest priced factory brass from RWS. The 8x64 is only available cheap and worthless from Sellier & Bellot, or expensive, really expensive from Brenneke.

Regards,

Fritz

---

Herr Kraut, who has an 8X60 reamer, bitte??

El Deguello

I am unaware of anyone who makes brass stamped for 8mm-06 or 8x63. He would have to use .30-06 brass, which is a military cartridge. I would assume that the brass is hard to come by (or illegal) in France if such rifles are banned.

If I may play advocate for a moment...

He could also use 25-06, 270 Win, 280 Rem, 338-06 A-Square, or 35 Whelen brass to form his cases from. While the 30-06 is clearly a military cartridge, its derivatives are not. All should be available through mail-order if nothing else and I doubt any of them are terribly hard to find.

The other solution I might offer would be to have your gunsmith make an 8x68s out your rifle. Definitely a European cartridge and never a military chambering...

quote:

---

Originally posted by Tex21:

The other solution I might offer would be to have your gunsmith make an 8x68s out your rifle. Definitely a European cartridge and never a military chambering...

---

I don't think the 8X68S fits in the standard length magazine and the bolt face would require substantial modification as well. Maybe someone can confirm this.

8x60 is obviously the historical way to go, as many original mausers have been converted for the very same reason.

The problem is that all the reamers are in Europe. You would need to procure one over there and send it to the US so that your rifle can be rechambered before shipments.

In the meantime, I have contacted Clymer to see about having one made up. It is about time I had access to one.

quote:

---

Originally posted by El Deguello:Herr Kraut, who has an 8X60 reamer, bitte??

---

http://www.triebel-guntools.de has reamers for the 8x60S.

As someone has remarked, this conversion from 8x57IS to 8x60S has been rather common in Germany before WW II. It´s notable that the Germans often spoke about the "8x60 S Magnum" or "Magnum-Bombe".

Fritz

Guys, I have ordered an 8x60 reamer. Anyone wanting to rent it just let me know. It'll be here in about 30 days.

Just a little historical note for the interested. If my sources are correct, the 8X60S became in vogue after the Treaty of Versailles (WWI) when Germany had to disarm under the terms of the treaty and 8X57IS, or JS as it usually called in the USA, became a target under the provisions of the treaty. Since France passed their first restrictive gun laws (1939) which restricted military calibers, the 8X60S also got a push for conversions of K98's. So Germany initially and France post war made this rechambering a popular option.

For those who would like to see what an original Oberndorf Mauser looks like, see below:

There is a third way! Since the scope mounts entirely on the receiver you can carefully remove and store the original barrel and replace it with one of a suitable caliber. If you rechamber this gun as-is it will probably lose an amount of value equal to or greater than the cost of the different barrel. The only other expense may be re-proving before it is released to you for use but that may have to be done if you rechamber it as well.

Tiggertate,
Technically you are right about the reproofing after rechambering, at least under French regulations. Chances are however that if I bring it through customs as an unrestriced caliber they probably won't ask that I do anything. I don't know what a riflesmith in the USA would require.

As for rebarreling, I'll check with a riflesmith. If I were to ever want to go back to the original barrel, do you think it would reseat to exactly the same spot with the original sights lining up correctly?

Wait! There's fourth way! I have a perfect MODEL B like yours with newer claw mounts and a Ziess 3x9 except some dickhead rebored and rechambered it to 35 Whelan
Let's trade so at least one of them can be saved!

Yes, it is not too difficult to reindex the barrel. Worst case might be taking a tiny (and I mean TINY) amount off the barrel shank to get it torqued up. Usually that isn't required.

quote:

---

Originally posted by Wink:
For those who would like to see what an original Oberndorf Mauser looks like, see below

---

Wink, with all due respect, that doesn't look like any Oberndorf sporter I've ever seen. I believe it's a sporterized military rifle, done similar to factory Oberndorf sporters.

Tiggertate, it always warms my heart to read the generosity the AR members extend to each other, but I'll take a rain check on the 35 Whelan. Since I'll probably never ever sell the thing I will look into rebarreling. I am able to daydream about calibers for a long time so that will be my next dilemma.

Fla3006,
When my brother gets back home I'll have him also photograph the Oberndorf Mauser blaser on the back of the receiver. He forgot to take that picture and went to Chicago for the week. My father liberated this particular rifle in 1945 just before the end of the war in Czechoslovakia from a physician/hunter when they collected all the firearms in the town the 1st Infantry Division liberated.

Yeah, some of us are just made that way

That does look like a sporterized model 98. It would say Obendorf a/N where is reads Mod 98, and there would be B and U proof marks near the serial number. That number doesn't look like it is from the commercial series either.

If you are referring to the Mauser banner being on the rear bridge, a lot of military contract rifles were stamped that way, since the country crest would be on the front ring.

Fla3006 and KurtC, You guys may be right and it may be my wishful memory at work. I haven't looked at the rifle in years so I guess I'll wait for the photograph next week. I will keep you all posted on this as if it is (as I remember) an Oberndorf Mauser you may be able to tell me something about this particular model. If it's not, than at least I don't have any ethical issues about rebarreling or rechambering.

The one I have has "Mauserwerke Oberndorf" stamped on the side of the receiver (where this says "M98"). Hardly conclusive, but still... I'll leave it it up to the experts.

Mine also hase the thumbhole cut-out - I guess that just means it was not made on a commercial action??

- mike

Oberndorf Mauser commercial rifles still retained the cutout on the left (as well as the stripper clip guide) right up until the end. It redirects gas and allows you to single load much easier. I have heard that some magnum length actions were made with a solid wall, but I have never seen a pre-war example of such and cannot swear to it.

Brno began leaving the left wall solid on commercial rifles in the 1930's, but they retained the stripper clip guide. FN and others also eliminated the cutout on post-war commercial rifles, but this was done as a cost cutting method.

If I might add, it looks like a converted milsurp to me too but, it still may be an Oberndorf. If it has the byf or 42 mark on the front ring then it was made by Oberndorf, for the military at least.

The gun turned out to be an "I" sporter rather than the "S" bore size, as I gather now from another posting of Wink. I do not know whether Triebel also has "I" reamers.

Regards,
Carcano

Instead of screwing with the gun, move out of France!

Moving out of France is always an option of course. I'm thinking about South Africa. Given that the rifle is not an Oberndorf and is in that wall-hangar of a caliber, I will probably just re-barrel and rechamber. I'm thinking about a 9.3 x 62.