Which action?

[Aescobar17]

Any custom actions that offer a .440 bolt face?

 

[IowaGeologist]

Zermatt/Bighorn.

 

[DairyDictator]

For that bolt face, I'd get a Bighorn. If/when you go to either sell or change calibers, pretty much any other caliber will need a different bolt face. If you went with something with a one piece bolt head, you'd need a whole new bolt instead of just a cheaper face.

 

[NWnewguy]

American Rifle Company makes bolt heads that size as well.