I disagree. Here in Canadaicon, 7.62 isn't cheap and plantiful, so 6 to one, half a dozen the other.

7.5 Frenchicon brass is readily available from hornady and you can also make it by simply running 6.5 Swede brass through a 7.5 sizing die - no trimming required.

Just use 7.62 Data of the purpose-made data from Hornady.

i don;t have the MAS49, but I do shoot a MAS36 from time to time and they are a nifty rifle with a very capable round that in many ways has a slight edge over the 7.62 NATO (which the Americans basically copied from the 7.5, changing it just enough so it wouldn't be the same... lol. Same bullet, same load, slightly smaller base and slightly different shoulder angle - that's it!).