.43 Spanish and .44-77 Rem., are the same cartridge?

I was talking about them with my friend Fernando and he thought it was the same cartridge, one military and the other sporting.
Looking on Donnelly book they have slight differences but look very close.
I have measure some Remington rifles with .446

COTW says that the 44-77 remington is “based on a combination of the 42 russian and the 43 spanish”.So,according to Barnes,the two are not interchangeable

Did you finish your article about 577 NE cartridges?

Yes, it was published last week.
I thanks those that helps me.