In France, we have 2 factories that load big bores.
The biggest one is Sologne.
Cartouches Sologne propose depuis plus de 15 ans des munitions de grande chasse rigoureusement précises et régulières fabriquées en France
www.cartouches-sologne.fr
Back to 90's, Sologne introduced the GPA, a lead free bullet with bands, that works like the Cuting Edge Bullet Raptor. They also produce a Round nose Solid up to 620".
In addition, they also load bullets from many companies like Nosler, Barnes, Hornady, Sierra, Woodleigh and Degol.
On their website, they produce ammunitions up to the .500 Jeffery and the .505 Gibbs, but on request, they can load bigger calibers. For example, Sologne was the factory that load the 700 Nitro express ammunitions for Verney-Carron.
But my only little complain I have is the French powder they use. I don't like it because it might have big variations from lot to lot. Normally, every batch should be tested in the Saint-Etienne Proof house but once, I had a surpressure with their ammunition that stuck the bolt of my Merkel RX Helix and I know several people who had the same issue.
The other factory is Sauvestre.
www.sauvestre.com
They have an interesting lead free bullet. I have only used the EXR in .375 H&H magnum, loaded by myself, and it worked great.