I just want to thank so many of you for your input in this thread.
@Riflecrank,
@Northern Shooter,
@CZDiesel and so many more. I recently acquired my first 458 Win Mag in a Model 70 Super Express with a 22' barrel. Prior to this my Largest caliber shooting was handled by my 300 Weatherby Magnum, so this is a jump in size. I have only shot about 30 rounds as I start to sight it in and get used to it. It needs some modifications the trigger being the next thing I am doing as well as others. I do hand load but not the 458 yet as I am just accumulating brass to do so. This gun is being built specifically for my next trip to SA for a Cape Buffalo in 2026. so I have time to figure out what the gun as well as myself like to shoot. I have gained more information on this caliber reading this today than the last 3 months reading everything I could find on the 458 Win Mag and I will defiantly try out several of the load s recommended or referenced here in. So Thank you all again for your sharing your wisdom and experience some of us GREATLY appreciate it!