There was a guy there who said he had almost all the Weatherby calibers and preferred to use Hornady bullets (Interbond) w/ R22 powder. He said Roy Weatherby designed his rifle for Hornady bullets because Hornady was his best buddy. I'm going to give it a try someday, but like I said, the Barnes X works well and has killed 4 bull elk from 100 - 300 yards out
Awful old subject but I just finished reading a great piece on bullet failure in the Africa part of "Graybeardoutdoors". The Hornady Interbond and Swift bonded core seem to be the bullet's to beat. The largest ammount of failures on African game come's with the Barnes X. You guy's might want to go there and read it.
I've never reloaded any Weatherby but have a theory on magnums. They are best when used to deliver extrodarnary power at normal ranges rather than normal power at extrodary range. Therefor in magnums I have loaded for, 7mm Rem and 338 Win, I always opted for the heaviest and tuffest bullets. In the day's I did those, I used only Speer Hot cores, a bonded bullet. Shot into dry newapaper, they never came apart and alway's maintained 85% or better of their weight. That at 100 yds.