It's a 7x54 MAS Fournier.
Mr. Fournier, at Hery sur Alby, Haute-Savoie, was a National 300m shooter and a gunsmith who make a job in rebarelling MAS 36 in 7mm/284" and chambering them for his own wildcat, the 7x54 Fournier that was a light modification of the 7,5x54 original round.
The 7x57, as all other army cartridges (30-06, 8x57, 6,5x54, 303...) is legal in France from September 2013. Now, the only forbidden cartridges are the .233 NATO, the 7,62x39, the .50 and 13mm Russian.

DORLEAC
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