It is a funny thing . I have been hunting now for 68 years , 10 of those years as a professional shikaree . In the last 68 years , l never personally seen or even heard of a single brand of .458 Winchester magnum calibre factory loaded ammunition accomplish the velocity that was advertised on the box .
During our time , the only 2 brands of factory loaded ammunition available for the .458 Winchester magnum were Winchester and Remington ( from 1961 onwards ) . Hornady bullets were available as a hand loading component .
The Winchester and Remington ammunition of the 1960s were advertised as accomplishing a velocity of 2130 feet per second . Unless you were using very freshly loaded ammunition , these velocities were optimistic by about 50 - 100 feet per second . By 1973 , the advertised velocity was lowered to 2120 feet per second . Again , unless you were using very freshly loaded factory ammunition , the actual velocities were around 2040 feet per second .
In 1978 , the advertised velocities got lowered to 2040 feet per second , in an attempt to increase shelf life . Not only did this decrease penetration for frontal brain shots on big bull elephants , but the actual velocity was often still lower than the advertised velocity ( around 1950 feet per second ! ) .
According to a book I own , " Ballistics in Perspective " ( written by a professional African elephant culler ) , the only brand which found a way to get the .458 Winchester magnum to deliver the advertised velocities , was A Square . In 1984 , A Square supplied the Zimbabwe Department of National Parks and Wild Life Management with a batch of specially loaded .458 Winchester magnum ammunition , using Remington Peters cartridge cases and Hornady 500 grain solid metal covered bullets . These delivered the advertised velocities of 2130 feet per second . Unfortunately , shelf life was lessened once again and after a few years of staying loaded , velocities dropped to around 2050 feet per second . In 1991 , this ammunition was scrapped and then A Square began supplying the parks with ammunition , loaded with 465 grain monolithic solid bullets , claiming an advertised velocity of 2200 feet per second . After a few years of storage , even this ammunition began to develop erratic velocities ( around 1970 feet per second ) .
I attach below , an extract from the aforementioned book .
Another brand which was reputed to deliver the advertised velocities in their .458 Winchester magnum calibre ammunition was Speer , with their " Grand Slam Solid " tungsten core solid metal covered 500 bullet.
@Ridge Runner , your best solution would be to hand load your own ammunition with 480 grain Woodleigh bullets. It gives you the powder space necessary to accomplish a higher velocity , although lighter for calibre bullets always compromise sectional density . I agree with Doctor Ray .
