Showing off my berthier

[vintage hunter]

the Balle 'D' ammo, which was a 198grn .323dia

Balle 'N' which was a larger diameter bullet

This is a popular misconception. The 1932N cartridge has a heavier bullet(232gr vs 198), powder charge and produces higher chamber pressures than the Balle D but maximum bullet diameters are the same, .328''. Besides weight and construction the biggest differenct between the two bullets is the location of their maximum diameters, The solid copper lathe turned Balle D bullet has it's max diameter located above the crimp groove and the lead core cupro-nickel jacketed 1932N bullet has it's below the crimp groove. This location causes the 1932N cartridge to have a larger neck diameter than the Balle D.
This is what makes it dangerous to fire 1932N cartridges in unconverted rifles. The neck portion of an unconverted rifles chamber isn't large enough to allow the N cartridges case neck to expand sufficiently enough to release the bullet and will produce chamber pressures higher than normal.
Since we're showing off our Berthier's here's my unconverted M1916 St. Etienne carbine made in 1918. It's all matching and appears to have escaped all of the post WWI mods/upgrades.