8x57j vs. 8x57JS vs. 8.57 "Norm"

[mauser22]

Perhaps not the best place for this inquiry but I recall this being discussed before and perhaps someone has already solved the mystery. Apologies in advance to Mods - move delete as you see fit.

I lucked into a July 1940 Type B yesterday. The gun had a late war 98K sling on it, so perhaps that excuses posting here.

I know that Olson stated 8x57 "Norm" is the .318 bore vs. the .323 of the 8x57JS as used in 98K.

I understand to be certain best to have it slugged. I just had 2 questions though.

1. Has anyone gone that route (slugging) already on a wartime Oberndorf sporter so marked?

2. Why in the world would Mauser chamber one in 1940 for the J bore (.318) if that is what this is?

pics

 

[Base2]

I beleive the 8x57J was the first version of this round and was made in the early Mauser rifles. It had a bore diameter of .318". Later the designation was changed to the 8x57 JS where the bore diameter was increased to .323" and the cartridge loaded to higher pressures. It is considered rather unsafe to shoot the "JS" ammo in the "J" bores as dangerous pressures can result. One needs to know the bore size to get the proper, and safe, ammo. European 8x57JS ammo is loaded to much higher pressures and would be very unsafe to shoot in an 8x57J gun. The U.S. manufactured 8x57 ammo is loaded to such low pressures it "SHOULD" be safe to use in the old Mausers but the guns are of such varied construction with "mix and match" parts (especially the very inexpensive surplus guns that are hitting the market) that the gun should be checked for headspace, soundness, and parts compatability by a qualified gunsmith before use.

 

[mauser22]

Yes I got all that. Not my first rodeo I assure you. Have checked headspace with forester gauges is perfect. Plan to slug it today and will report findings.

I just thought somebody might have already done that on one of these late guns.

Possible was special order in the J bore,, or M-O might have been using up left over barrels.

Horror of all horrors, I do plan to hunt with it unless I have to custom load or cast bullets.

 

[Muncher 1953]

Yes I got all that. Not my first rodeo I assure you. Have checked headspace with forester gauges is perfect. Plan to slug it today and will report findings.

I just thought somebody might have already done that on one of these late guns.

Possible was special order in the J bore,, or M-O might have been using up left over barrels.

Horror of all horrors, I do plan to hunt with it unless I have to custom load or cast bullets.

Looks like a beauty, it was made for hunting, so why not?

&YES, I’d slug it first!

 

[mauser22]

first test only

Not enough lead on hand to make a good plug but flattened a 00 buck pellet enough it shaved circumference when tapped in muzzle to a depth of about 2 inches. Knocked it out with a .250 wood dowel. Pellet too small to hold and use mircrometer, so I set it at .318 and locked it. Pellet would not pass through. Reset micrometer in .001 increments until the pellet would pass through at .322

I don't consider this final judgement and will report when I do a proper job of slugging the bore length.

But it appears it may indeed be 8x57JS vs. J bore which the "norm" infers.

 

[mauser22]

Final verdict is in. I obtained some sinkers that gave ample length and dia for good measure after a full length pass through bore.

I must have been cocking the little 00 buck pellet as 2 plugs made from the sinkers both measure dead on at .319. That is the J bore and is often marked on barrels as "norm".

So will not be custom loading to hunt with it. She is one fine addition to the collection though as only about 3K centerfire sporters made during the war.

Out of curiosity, I also slugged a standard 98K barrel (8x57JS) and the slug measured point on .323

Perhaps a special order or using up left over barrels, but I am inclined to think it was sabotage to keep some Hillbilly from using it to deer hunt.

Oh well I have a nice German built sporter on a 98K that has already taken some whitetails.

 

[mauser22]

Feeling like an idiot and senile for sure. Review of Jon Speeds "Mauser Sporters" indicated none made in 8x57JS after 1920. Then the reason hit me. Production of rifles in the standard "Infantry" caliber (8x57JS in the Gewehr) prohibited by the Treaty of Versailles. So Mauser abided by this to the end on sporter production. As an alternative the 8x60 cartridge much more common from 1920 onwards. Those not marked 8x57 NORM marked 8.0 N. Duh!! Plus the answer was in plain sight. Barrel bottom marked 7.85

Never stop learning. A case of letting what you know get in the way of what you don't. When I saw 8x57 I got excited. Would not have influenced my purchase though. As is the case on all these it's a piece of art.

I see them listed for sale occasionally and currently as being 8x57JS - upon examination of photos in all cases, they ain't.

 

[Muncher 1953]

Feeling like an idiot and senile for sure. Review of Jon Speeds "Mauser Sporters" indicated none made in 8x57JS after 1920. Then the reason hit me. Production of rifles in the standard "Infantry" caliber (8x57JS in the Gewehr) prohibited by the Treaty of Versailles. So Mauser abided by this to the end on sporter production. As an alternative the 8x60 cartridge much more common from 1920 onwards. Those not marked 8x57 NORM marked 8.0 N. Duh!! Plus the answer was in plain sight. Barrel bottom marked 7.85

Never stop learning. A case of letting what you know get in the way of what you don't. When I saw 8x57 I got excited. Would not have influenced my purchase though. As is the case on all these it's a piece of art.

I see them listed for sale occasionally and currently as being 8x57JS - upon examination of photos in all cases, they ain't.

a bit off your topic, but have you noticed how many rifles that are actually 8x57JS are listed at auction as “8x57JRS” ?
(The rimmed version of 8x57) I see it all the time on auction sites, it drives me crazy! (not that I had far to go) If it isn’t an M95 or a custom like yours, I just ignore it, but it makes me think less of the seller. As if they’re all copying & pasting the same erroneous info, come on people, these are FIREARMS, get it right!

 

[flynaked]

Military cartridges were still forbidden in many countries, which is a lot of the reason behind commercial makers often opting for the .318 bore from what I understand. A Normalisiert chamber is actually a hybrid of the two, the neck and throat are opened more along the lines of the .323 dimensions.

 

[mauser22]

Thanks for all that!

Well I suspect a lot of .323 JS ammo has been put through some of these and it's a tribute to Paul Mauser you don't hear about more incidents resulting - Due to all that. That also explains why my gauges for JS worked and why when I chambered a fired JS case it came back out the same neck O.D.

You also see a lot of drillings listed as either just 8mm or 8x57JS when they are 8x57JRS or 8x57JR