I’m writing this from a completely neutral and unbiased point of view. Because while the .458 Winchester Magnum certainly isn’t my favorite caliber, it definitely isn’t my most loathed one either. I actually hunted twice in Africa during the 1970s ( the first time being a mixed bag safari to Kenya in 1974 ) and I have seen first hand exactly what the firearms situation was like, back in those days.
Yes, almost all the white hunters in Africa during the 1970s were using a .458 Winchester Magnum caliber rifle as their primary dangerous game backup. However, it must be borne in mind that this was more out of compulsion rather than by choice.
After World War II ended, ICI ( Imperial Chemical Industries ) Kynoch ( who was the SOLE manufacturer of factory loaded ammunition for British big game large caliber rifles ) had begun to discontinue all of their product lines steadily ( since the British empire had begun to lose all of it’s colonies where big game could be hunted and thus demand began to drop for these large bore calibers ). By 1957, they had already discontinued the .416 Rigby and the .425 Westley Richards and the .505 Gibbs. By 1963, they had discontinued the .476 Nitro Express and the .600 Nitro Express. By 1969, ICI Kynoch only offered ammunition for four big bore calibers: 9.3x62mm Mauser, .375 Holland & Holland Rimless Magnum, 10.75x68mm Mauser and .404 Jeffery. In 1971, ICI Kynoch had completely bulldozed their factory and ceased manufacture of all center fire ammunition without exception.
So during the 1970s ( precisely 1971 to 1981, after which Jim Bell in the U.S.A began to produce factory loaded ammunition for the previously obsolete British big bore calibers ) , those who wished to hunt big game were limited to four choices:
1) .375 Holland & Holland Magnum - Factory Ammunition produced by Winchester ( a dismal 300 grain Silver Tip soft point and an even worse 300 grain lubaloy jacketed flat nosed FMJ solid ), Remington ( a 270 grain Core Lokt soft point and a 300 grain round nosed steel jacketed FMJ solid ) and RWS ( a really good 300 grain TUG soft point and a really strong 300 grain round nosed steel jacketed FMJ solid )
2) 10.75x68mm Mauser - Factory Ammunition produced by RWS ( a very very poorly constructed 347 grain round nosed steel jacketed FMJ solid )
3) .404 Jeffery - Factory Ammunition produced by RWS ( a very very poorly constructed 400 grain round nosed steel jacketed FMJ solid )
4) .458 Winchester Magnum - Ammunition produced by Winchester ( a poorly constructed 510 grain soft point and an even worse 500 grain round nosed cupronickel jacketed FMJ solid ) and Remington ( a 510 grain soft point and a 500 grain round nosed thin steel jacketed FMJ solid )
For obvious reasons, I didn’t include the .378 Weatherby Magnum and the .460 Weatherby Magnum in the list. Given the availability of factory ammunition in these four calibers, it goes without saying that the 10.75x68mm Mauser and the .404 Jeffery were not often chosen during this time. So that essentially left hunters with two choices:
1) .375 Holland & Holland Magnum
2) .458 Winchester Magnum
Understanding the limitations of the .375 Holland & Holland Magnum as a charge stopper in thick cover, most African white hunters had NO CHOICE but to go for the .458 Winchester Magnum. Indeed , I made the exact same observations as Col. Charles Askins did when I visited Kenya in 1974. Every white hunter I crossed paths with, had a .375 Holland & Holland Magnum and a .458 Winchester Magnum in camp.
My white hunter, Joe Cheffings had a BRNO ZKK602 in .375 Holland & Holland Magnum and a BSA Majestic in .458 Winchester Magnum. He used the BSA Majestic as his backup rifle, while I borrowed the BRNO ZKK602 for hunting the dangerous game elements of my safari ( using RWS 300 grain TUG soft points and Remington 300 grain round nosed steel jacketed FMJ solids ). On my 1978 safari, my white hunter was armed with a Remington Model 700 in .458 Winchester Magnum ( and he openly told me that he would much prefer a .416 Rigby ).
From 1982 onwards, big game hunters began to slowly gravitate towards other calibers as soon as factory loaded ammunition for them began to be available ( such as the .416 Rigby ). For example, Walter Johnson eventually had his .458 Winchester Magnum caliber pre 64 Winchester Model 70 rechambered to .458 Lott.
Also, the information about Wally Johnson ( Walter Johnson’s father ) eventually switching his .375 Holland & Holland Magnum caliber pre War Winchester Model 70 for a .458 Winchester Magnum caliber Model 70 is incorrect. This was a rumor that was perpetuated by Jack Lott in the January 1972 issue of “ Gun Digest”. Wally Johnson later allowed Peter Hathaway Capstick to interview him and write his biography in a book called “ The Last Ivory Hunter: The Saga Of Wally Johnson “. In that book, Wally flatly denies ever personally owning a .458 Winchester Magnum. We goes on to claim that ” I will always consider the .375 Holland & Holland Magnum to be the only gun “. This biography was written at least 14 years after Jack Lott wrote that article.
John Kingsley Heath too was forced to abandon his beloved .470 Nitro Express rifle once ICI Kynoch ceased to manufacture ammunition for this caliber in 1968. He too was forced to switch to a .458 Winchester Magnum custom rifle, which was built on a pre ‘64 Winchester Model 70 action with an extended drop box magazine. That rifle may be seen here :
https://www.christies.com/en/lot/lot-1013119