8x57IS vs 8x57JS

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Andreas

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Hi Everyone,

I am looking at getting a CZ550 Lux in 8mm Mauser and they offer it in 8x57IS. http://www.czub.cz/en/catalog/81-centerfire-rifles-cz/KM/CZ_550_LUX.aspx

Can anyone please educate me on the differences between 8x57IS and 8x57JS?

And also where I can find ammo for this rifle as all I can find on site sponsor sites is the S&B and PRVI Partizan ammo and they are only labelled as "8x57JS" and "8mm Mauser" respectively. Can I use 8x57JS in this rifle (8x57IS)?

Many Thanks!
Andreas
 
One rifle bore is smaller than the other, and cannot safely shoot the large (.323 diameter) bullet. They are not the same.
 
fiddler said:
One rifle bore is smaller than the other, and cannot safely shoot the large (.323 diameter) bullet. They are not the same.
Click to expand...

No. IS/JS same thing. Different style of script for the I and J. Both are .323. It is the "I" alone, without the "S" that is .318.
 
IS and JS are the same. Actually, the "I" was written in a "J" shape when the Allied took up the arsenals, hence the confusion. "S" is for "Spitzer"(Spitzgeschoß). 7.92X57, 8X57IS, 8X57JS and the anemic 8X57 Mauser in the US are all the same name using the .323" bullet.

8X57I is the .318" bullet.

BTW, the picture showing various caliber in the Wiki article is from me...
 
Thanks very much everyone... clear as mud!

I also have just recently aquired a 1942 98K Mauser and just want to confirm that I can also use the 8x57IS/JS (.323) or is it the 8x57I (.318)?
 
I must disagree with you Baribal on this matter, the "S" does not indicate "spritzer" in this case. It does in fact indicate the last incarnation of the 8mm cartridge being of .323 bullet diameter. All .323 diameter cartridges carry the "S" designation (in Europe) regardless of bullet shape and if the "S" designation is not present in the cartridge name then it is assumed to be the earlier .318 diameter bullet. Regardless of any other letter in the 8mm cartridge designation, if the "S" is present it IS .323 diameter. What we in NA call the 8mm Mauser is correctly referred to as the 8X57 JS. We just assume when speaking of the 8mm Mauser that everyone knows it's the .323 incarnation.
 
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Nope, Baribal is correct. When Germany adopted the IS/JS cartridge the S did indeed indicate Spitzer. The phrase S-bore has since been used in Europe to indicate .323" groove dia. and bullets, even on non military calibers eg 8x68S.

European ammunition commonly carry the IS designation.
 
tiriaq said:
No. IS/JS same thing. Different style of script for the I and J. Both are .323. It is the "I" alone, without the "S" that is .318.
Click to expand...


I've been properly corrected. The only .318 ammunition I've ever seen is in my Fathers antique cartridge collection, but there are still lots of old .318 diameter rifles around. Anything pre-WW2, I slug the bore after a good cleaning to be sure of its diameter.
 
c-fbmi,
As Windknot said, the "s-bore" disgnation comes from .323" spitzer bullet used for the 8X57IS, the "S" later being adopted to differentiate the caliber from the old .318" RN.
 
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I try and remember it by .318 with I being the 1 in between the 3 and 8.
The IS taking the S to represent the 2 in the .323. The S and 2 sort of have the same shape.

Well it works for me tete..... :wave:
 
Andreas said:
Thanks very much everyone... clear as mud!

I also have just recently aquired a 1942 98K Mauser and just want to confirm that I can also use the 8x57IS/JS (.323) or is it the 8x57I (.318)?
Click to expand...

See your Friendly Neighborhood Gunsmith and get the straight skinny from him/her.
You may feel your experiencing muddy information, but it would be much safer for you
if you where to get a hands on explanation, yes?
Rob
 
Correct me if I am wrong, but didn't the S bore predate the Patrone S? The S in Patrone S being for spitzer.

Wasn't the G88's 318 grooves first deepened to 323 and marked with a Z, then new barrels with the Z groove depth marked S?
 
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