I am a strong believer in the Barnes X bullets and have used them extensively in my .223,30-06 , .416 Rigby and my .458 , all recovered bullets showed good expansion.
When Barnes launched their X Bullet in 9.3mm I bought some immediately as there were not good bullets available at the time for the 9.3 . I load them with 52g of Somchem S335 for 2270ft per second.
This very topic came under discussion once at an AIM Show some years ago when a hunter told me about his custom-built rifle. Even when his decision to have a custom rifle built was conceived, his mind was made up that it would be in a true South African caliber. But prior to actually suit the action to the word, he spent many hours contemplating what a true South African hunting caliber would be.