I wanted a .416 Rigby in a CZ550 when I went to Tanzania three years ago....none was available locally ,but I got a deal on CZ550 Safari Magnum Express in .458 that was too good to pass up.I called Barnes and they recommended a load with H4895 and their 450 gr. TSX which chronoed 2170 with the bullet set out closer to .458 Lott specs.That rifle has a longer magazine box than most .458 Winchester chambered guns. It fed very well and my first shot came at 103 yds. (lasered). It was a complete passthrough on a broadside shot just behind the shoulders.
Unfortunately, I shot just a hair high and the job required three follow ups.He was dead on his feet,but he didn't know it. They were all from straight on in the front and all penetrated completely to his hips through a full paunch. All mushroomed perfectly.When the skinners dug in to retrieve my bullets,I couldn't believe all the grass.
With TSXs,penetration with the .458 will be everything you need.As always,bullet placement is the key.
