I'm not a bona fide reloader myself, but I have reloaded some with my brother. I can remember one instance that does match what you are saying about the norma brass. It all fits, and I believe you.
I once had a 9.3x74, wish I still had it. I think I have about 5 boxes of Norma with the 232 grain bullets, or something close to it.
Now I wish I had a rifle to go with it.
I think it would be a non issue for Norma brass, "if" the cartridge has a decent "shoulder" and was kept to lower pressures. The problem is, the 9.3x74R has almost no shoulder, and unless your extremely carefull you get excessive case stretching with there brass.
In a bolt gun or something like a Ruger #1, when you push the pressures up, then new problems crop up...like loose primer pockets...
I have a double and a combo in the 74R, but i designed an "improved" reamer and my double is now an 9.3x74R "improved". Here's a pict of the factory 74R case and the imp. version, both loaded with 286 NP's...
I did all of this long ago, and it's still on my "to do" list to wring the new chamber out...
DM