The .458 will recoil harder as pressure and velocity increases which, as a statement is too simplistic to generate value, as all cartridges will do same. What I need to convey is that 100fps can have impact on recoil perception with the .458 much more, than most other cartridges.
I've found the above to be very true of the 458Lott as well. Working up loads the rifle 'all of a sudden', literally at 82gr of powder, really came alive off the bench! In a 10.5lb CZ this was noticeably more disconcerting than a 9lb Zastava 458WinMag and its 500gr Woodleigh at 2060fps. My 470Capstick does the same thing, really coming back hard as top-end loads are approached. Oddly ... a 458AccRel (shortened/opened 300RUM) is not as painful even with a 500gr at 2230fps and that rifle is still wearing its factory Ruger pad and a barrel that brings weight to 10.5lb.
Best thing I ever did with my 458WinMag was to load 350gr Hornadys to 2400fps and go hunting. Later and when used to the rifle, I started trying the 510gr loads. By that time it was noticeably more recoil, but not uncomfortably so. After you've mastered the 458WinMag etc ... the "horribly kicking" 8mmRemMags etc start to feel like pop guns.
Cheers...
Con
