The rumor mill is whirring about Ruger and Hornady reps in Zimbabwe right now testing the 416 Ruger cartridge on lion and various other game. I'm guessing it is probably just the 375 Ruger necked to 416 without any other changes...

Should be very similar to the 416 Rem Mag in performance.

This should make a dandy African rifle and on a standard length action. I've still got that friend whom plans on going in 09. I'll pass on the info. He's looking at a CZ 416 Rigby right now. It's a lot of gun for the money.