I'm not sure if anyone mentioned Black Hound??
I've got one on a 22 and another that is goin on a 300 Rum.
I called them a couple weeks ago and asked how they do on large magnums. They suggest not using the mounting rings that are supplied, and instead going with something a little more proven. He had tested the Evolve 5-25x56 and out of 10 different rifles, he lost zero on two of them due to proprietary rings. That's why he is recommending better rings when mounting on large mag's. Any other caliber is fine with black hound rings.