Home Forums Hunting & Shooting Express Rifles and Big Bores Only The great 458 Winchester. Everyone should own one at least once

Sir Ron, this thread continues to provide useful insights into so many issues about the 458 Win Mag. Thanks for your continued efforts.

I had read about isolated ignition problems in the early years but I did not realise that this was a persistent, widespread problem (in Africa) over many years. Shelf life of 458 Win Mag ammo was a huge concern as savvy users insisted on freshly produced ammo. This raises a few questions:

1. Did other cartridges suffer the same problem or was it isolated to the 458 Win Mag. You only ever hear of 458 Win Mag ammo problems.

Might have something to do with volume of ammo produced by yayhoos at the defective factory and
the volume of that same ammo subsequently abused by yayhoos in the field.
It was a popular cartridge until the yayhoos screwed the pooch.

2. I suspect it had to do with powder compression and perhaps the primers used that might have lead to ignition problems. In those days magnum rifle primers probably weren’t widely available and more to the point, did Winchester even make a magnum rifle primer back in the day?

Defective powder lots and defective loading techniques by the yayhoos.
Reports abounded of factory loads with mixtures of ball and extruded powders in different cartridges in the same 20-count box of ammo.
Reports have been heard of factory ammo machines run amuck and spilling as much powder as was loaded into the case.
Yayhoos take smoke breaks and have to get away from the line now and then.
Used to be the WLR primer from Winchester was for standard and magnum loads, including .458 WinMag.
Now they have the WLRM for magnum applications.

These days there are hotter primers for improved ignition and more suitable powders that can be loaded without compression, with some also being temperature stable. Add to this a wide range of better bullets and the 458 Win Mag is a better choice today than at any time in the past.