Shooting solids one would think the larger diameter of the 505 Gibbs would make it preferable.

Prior african lore and dogma of killing ability suggests Weatherby mantra of velocity++ doesn't hold up well on the big tough stuff.I would think their tissues would withstand the transmitted energy of a high velocity "soft" with hydrostatic incapacitation better than straight line penetration x the impact momentum of the larger caliber going to the vitals.

I have read the opposite problem may have happened with the 4 bores shooting lead balls.Great delivery of momentum and horrible superficial injuries but not enough penetration to the vitals for instant kills.

Smokeless powder, solids, 2000+fps velocity seems to be the combination that works the best.This would logically seem to make the 700 nitro better than the 600 as a stopper etc, etc.

I am just going to keep my 470 unless I find can shoot and handle a 500 as well. I believe 577 and up are out of most hunters envelope of tolerance to shoot and ability to make a f/u shot!!