Although the .338 Win Mag case has been necked up and down (i.e. .264 Win Mag, 7mm Rem Mag, .30-338, 8mm-338, 358-338, 375-338, .458 Win Mag) I have never heard of it, or any of the other belted mag cases, necked to 9.3 mm (i.e. .366). This is a rare bore in American, although it is more widely used in Europe and Africa, as a result of the old, classical medium bores in the form of the 9.3x57, 9.3x62, 9.3x64, and 9.3x74.
There are some really juicy 9.3 bullets made by Speer (270 grain semi spitzer), Nosler (250 Grain BT, 286 gr Partition), Woodleigh (250, 310 grainers), Swift A Frames (250, 285, 300 grain A Frame bullets) Hawk bullets (200, 235, 250, 300) and Barnes (250, 285 X bullets).
I think a 9.3-338 Win Mag would be kind of neat. Any body else have any thoughts?l