Please help identify 37mm round

[Dylan132]

Hello,

I got these two 37mm rounds in the post today and I already know that one of which was manufactured in Germany in 1918 (left). I also think the German round is an HE round as there is a hollow cavity in the projectile but I'm not too sure on this. Onto the my main question, can anyone please help with the identification of the second round (right). The one on the right has no markings at all, not even a headstamp.
Any info will be greatly appreciated.

-Dylan

[KradSpam]

The better marked one could be a naval round? I'm basing that on the M under the crown. WW2 Kriegsmarine kit is always marked with an M so perhaps Imperial stuff also? Just a thought as a starting point for research.

[Dylan132]

Thank you very much for the info KradSpam, after doing a bit of research i found this: 3,7cm C97/98 Cartridge Casing, explains basically everything on the German headstamp