I think it might be a Berdan-primd catridge by the picture，I wonder the information on the headstamp，and why is there a circular groove at the bottom of the cartridge case？I wonder that，too.
I was told the groove is to lodge the projectile tips of other cartridges when loaded in tubular magazines so they do not reach the primer (recoil may set off the primers in the magazine then). Also the reason why the M1886 projectiles were flat nosed.
One may correct me if I got mislead.
Sounds perfectly reasonable.
But then again, in my experience, “perfectly reasonable” is usually wrong…
Original Mle1886 Balle M, for the Lebel tube Rifle, were Flat nosed cylindrical bullets to prevent detonations in the Magazine Tube.
In 1897, Balle D was developed; a Boattailed Spitzer, for the Hotchkiss Mke1897 MG; it was also used in the Charger fed Berthier Carbines and Mousquetons of 1890/92
The Groove on the base of the Cartridge case was to lodge the Balle D point away from the Primer ( the double taper cases causes the bullet point to go closer to the magazine tube wall, rather than the central axis ( primer).
Several Primer Types were used, the am, or amorce modifie ( modified Primer) and the aa (amorce anglais-- English Primer.)
All were Berdan, major pocket diameter .240", Primer cup .250" ( interference press fit.)
By the Mle 1932 N ( lead core projectile, as shown OP,
The cases used a Double Primer cup ( outer .250, inner .217", with a lower than normal anvil…) all this for safety in the Hotchkiss Mle 1914 MG.
You cartridge was produced in 1948, by Societe Francais des Munitions, the Metal supplied by SFM’s own Brass Mill at Issy-les-Moulineux, an outer suburb of Paris, on the Seine ( Northern area). The SFM plant was next to the Mill — Issy dates from Middle Ages as a location of water mills ( Moulineaux) for grinding grain, and industrial work.
All gone now. ( redeveloped into classy residential)
BTW, this ammo came out of Syria
In 1980s ( Century Arms) and is mostly “dead” (primer decay). Packed in 24 round Hotchkiss feed strips.
The balle D was a solid bullet, made entirely of gilding with 90 percent copper.
The 1932N as shown is a conventional jacketed lead core projectile. It is heavier (15 g) as balle D (12.8 g) and intended for long range machine gun use, like so many types introduced after the experience of WW1.
Because of its 8.30 mm diameter, the 1932N projectile needs a case with a larger neck diameter. The rear part of balle D (the part within the case neck) has the old 8.15 mm diameter of the original 1886 bullet.
After the introduction of the 1932N, all rifles had the chamber neck re-reamed, to be able to use machine gun cartridges in an emergency. These rifles have an N stamped on the barrel.
It is basically the same re-reaming as the Germans did 1903-05 in connection with the adoption of the 7.9 mm S-bullet. But the French were spared the 8 mm chaos of Germany (every gunmaker did as he pleased), because military calibers were off limits in France. (I have not details concerning Russia, where the 7.62 mm bullet diameter was also increased mid-stream.)
Why was 1932N made 8.30mm wide? Why not 8.15mm? Was that done to make it heavier?
The French groove diameter has always been 8.3 mm. Making it heavier was not the goal. On the contrary, the increased bullet diameters were introduced with bullets that were significantly lighter
than the original French balle M, German 88 and Russian 1891.
First it was feared that new light bullets (French D, German S, Russian L) would not fill the grooves properly (called set-up). The much stiffer French brass balle D doubtless could be prone to this problem. So they were made as large as the existing groove diameter. [Frankly I speculate regarding the Russian groove diameter here.]
Then it was discovered that it was advantageous to make bullet and groove diameter as close as possible. Which is the way ammunition is designed still today.
When some nations started using heavy bullets of a new design (French 1932N, German sS or Soviet D), the larger bullet diameter first adopted with the light bullets was kept.