Cuz,
I would be willing to bet that it is the early Norma 9.3x72R Normal, it was sold in the 10 round boxes with RED label. I have several guns in 9.3x72R and some will only chamber about 1/2 way with the later rounds. Zip me an e-mail & I will shoot a picture of the boxes that you should be looking for & by the way I took a reading with a starett micrometer as close to the case as I could get & it measures approx .360 diameter.

M-4