I’ve got two Whelen and a 9.3x62 and can’t find much difference between the two of them. I’ve not shot Bullets heavier than 250 grains in either one yet, but I’m not going to be surprised when they’re about the same.
Twist as another fella mentioned means more than much else in my book. The 9.3 is a 10 twist and the one 35 Whelen is a 14 while the other is a 16. The Whelen easily topped 2600 and change with a 250 and RL15 and the 9.3 does the same with very similar powder charges.
Components are about the same to me on many sites for availability as well. I’ve taken bear, deer, and elk with the Whelen using the 225 TSX, 250 PT, 225 Accubond, 250 Speer and 225 Sierra GameKing. My only real problem bullet was the 200 grain Remington PSP that wouldn’t make it through a broadside deer, but otherwise the rest have been great.
I expect the 9.3 to act the same when I do use it.
