Little curious why they won’t make a good hunting action. I spent a significant amount of field use with my actions in temps and conditions varying from +30c or greater to -30c and lower. From matches, range session and hunting. I’ve never had one of my custom actions fail minus my vudoo 22 with eley ammo at a match that was -30c but that was also the ammo in those cold temps. I would trust any of my centerfire custom actions in cold weatherI get a kick out of hearing guys say that they hunt in extreme conditions, and then say that it was 0°F or something.
My son and I were just hunting late season elk in -35°C(-31°F). Failure to fire from the cold is starting to be a real possibility at those temps.
Not knocking all these recently introduced custom actions that are being mentioned, but they are mostly designed for the target range first and foremost.
Just get a good Mauser.