What are the factories still producing rifles in magnum length actions today?
Lets disregard for this topic, a subject of controlled round feed or push feed.
Also, lets disregard, shortened magnums (and 375 Ruger and other of similar concept).
So the question is, what factories still produce magnum length actions, regardless of type (CRF, or PF), for cartridges 375 H&H upwards?
One that comes to mind is Sako 85. What would be the others that you know about?
It might be easier to work back to the action type as one category, and then to mention the high-end makers that may opt to use that action for particular bespoke guns.
I don't know about the Sako 85 action type. Certainly there are remaining CZ550 Magnum actions in the white available even though discontinued. Weatherby has an action. Dakota has/had an action. Granite mountain has/had an action. Empire Rifles had the ability to use other's actions. I think Heym has their own proprietary action.
Then we go to the "true" magnum that founded them all. The single or double square bridge Mauser action. I believe three groups make them to Paul Mauser's blueprint. Prechtl, Reimer Johannsen, and Mauser. Manufacturers today like Rigby, Griffin & Howe, New England Custom Gun, and most of the "famous English firms" will procure one of those three square bridge magnums and build you a gun today for very large money. The actions in the white, run about $6000.