8mm Mauser vs 8x57JS ???

[slm9s]

Finally found a K98 Mauser at the fun show. Grabbed a set of dies and a guy had a bag of brass labeled "8mm Mauser." Got home and found that half are RP 8mm MAUS and half are Norma 8x57JS. I'm no expert, but I had thought that those were both names for the same cartridge, maybe the JS having a 318 bore rather than the 323. However, the brass I have, the Norma brass is about 4mm shorter than the RP. Is this normal, or did someone "alter" this brass?

 

[akajun]

Same case and the JS is the .323 bore
Norma cases are shorter , idk why

 

[Ggmac]

double check those Norma cases . They appear SHORT .

 

[philip brousseau]

I was thinking john Sandra but I think his were designated JRS

 

[SeabeeKen]

Same case and the JS is the .323 bore
Norma cases are shorter , idk why

This is correct. The chamber should be the same. The only difference I recall was bore size. Since shoulder has been moved as well as trimmed too short, I'd take some measurements to see which is the true 8X57. I suspect the shorter one was modified or wildcatted. Trash the wrong cases before they get mixed up and cause a headspace issue

 

[slm9s]

The longer RP cases chamber in the rifle, so I assume the Norma cases were shortened to be used in another chambering.

 

[Just Say Moe]

Could they have been modified to 7.65×53mm? Measure the inside neck diameter.

 

[SeabeeKen]

The longer RP cases chamber in the rifle, so I assume the Norma cases were shortened to be used in another chambering.

Are the rp the same length as the case length shown in the page from the hornady manual above?

 

[slm9s]

2.23 vs 2.11 for Norma
ID is .323 vs .311 for the shorter Norma ones

 

[SeabeeKen]

2.23 sounds good. Thats the trim length of 8x57

 

[Just Say Moe]

2.23 vs 2.11 for Norma
ID is .323 vs .311 for the shorter Norma ones

Uh.. 4mm shorter, .311 neck = 7.65 x 53 Argentine.......