I don't know about the 458, but I load and shoot a lot of rounds through my 45-70 Guide Gun. Recoil can be from moderate to brutal depending on the load and bullet weight. Even the moderate loads can give you an excedrine headache, after 10 or so rounds off the bench. A PAST shield helps immensely when benching Big Medicine! This has a lot to do with the light weight of the rifle. As the 458 is alot more gun, I rather suspect shooting this caliber out of a lighter rifle (say under 9 lbs) would be nasty, but less so if shot offhand. I'm uncertain, but I believe american production bolt action 458's are in this weight range...