I’m not a fan of extremely high speed in hunting bullets. At very high terminal speed, premium bullets tend to hold together better than cup-and-core bullets. At the speeds for which they were designed, plain bullets do very well. The old Remington Core-Lokt is a good example, and Sierra bullets are another.

That said, I still like to experiment with premium bullets. In the Ruger #1 RSI (270 Win) I was unable to get Nosler Partition bullets to shoot with sufficient accuracy. I happened to have some 130 gr Speer Grand Slam bullets, and was surprised to find that they shot with accuracy equal to Sierra bullets of the same weight.

The 30 Herrett, 10-inch Contender pistol will never be terribly hard on bullets, as it just cannot generate the speed. I finally settled on 150 gr Nosler Ballistic Tip bullets, as they gave the accuracy I need, and Nosler claims they will expand down to 1600 fps. Sierra bullets are too "hard" for this application, and would probably fail to open.

I’ve shot a lot of game with Sierra bullets, and have never had a failure to kill cleanly.