2.400", trimmed to 2.390"
Started with a 376 Steyr case.
Made some belting dies.
Then blew it out with Cream of Wheat.
With the 265 Hornady, it will fit into a 2.800" magazine.
The neck is too thin for the Hornady 444 dies, it doesn't hold the bullet.
44 Mag pistol should neck size it just fine.
Any way, I now have a 444 Marlin that can be used in a bolt gun, or AR 10.
Calling it a 444B
Holds 73.0 grains of H2O.