25 mm cartridge marked: MR/H 35 30 C (6.5" LONG)

I have a 25 mm brass cartridge marked MR H (on top), C (on bottom), 35 (left side), 40 (right side) . It looks WW1 vintage but I cannot identify country of origin or manufacturer. Any information would be helpful. Thank you.

That sounds like a 25x163mm Hotchkiss case made in France. This round was used in an anti-aircraft role.

  • MR indicates the manufacturer: Manufactures de Machines du Haut-Rhin aka MANURHIN.
  • C indicates the company that supplied the metal for the case: Compagnie Française de Metaux, Castlesarrazin, France.
  • 35: lot number.
  • 40: year of manufacture (1940).

The 25x163 Hotchkiss is shown below - it’s the fifth one along from the left, in this pic from the Ammo Photo Gallery on my website…

23-28mm CARTRIDGES TO 1945

25x87R Vickers Terni (WW1), 25x87 Revelli FIAT (WW1 aircraft), 23x106 (Madsen aircraft), 25x205R (Bofors for land and naval AA gun), 25x163 (French Hotchkiss for auto AA gun - aka IJN Type 96), 25x189 (Vickers 25.4mm naval AA), 28x199SR (USN 1.1" AA, repP), 24x138 (Swiss Pzw.Kan 38), 23x152B (Russian VYa), 23x115 Russian (NS-23)

Thank you so much for quick response. I am not familiar with the stamping marks. Do you think this was French made prior to ww2 or Japanese anti-aircraft ww2? Thanks.

It was made in 1940 in France, which at that point was involved in WW2.

Again, thanks for the great information and the quick response.