When you get 100% density, you have compaction. The case is full to the top, then you stick a long 450 or 500 gr. bullet in it, you have compaction.
These are not "old stories", it happens every year a couple of times. In my business we hear about it when it happens. It has happened with factory ammo. It has happened in our camp several times over the years and enough times that I won't hunt with the .458 Win.
For those that are convinced otherwise, that is there choice but I see no reason to position myself in that group, based on my own experiences, when I have so many choices, such as punching it out just a tad to a .458 Lott, and loading the Lott down and really lowering the pressure.
What I suggest is put that 100% density ammo on the shelf for a year, then pull the bullets, you will have to dig it out with a screw driver as a rule. I don't find it unusual that someone has good luck at the range in hot temps with compacted ammo, but then the gun has not been sitting in the sun for hours at a time as it may be in Africa.
As to killing power, I have no complaints with the .458, any bullet weighing 500 grs. at 2000 FPS will kill anything., but reliability in the field is foremost with me, as I have seen many cases where a hunter is in a precarious position and his gun jams, or misfires or doesn't fire, and he is playing switch finger while everyone else is sorting out his mess.
I also see a lot of loads for that caliber that just don't click on my chronograph and velocity is guessed and by goshed at.
The above is only my personal opinnion, your is yours. If you are confident with the .458 then by all means use it.
