I honestly wonder if anyone was ever killed using a magnum length Mauser when a standard length Mauser would have saved their life? Further if using a M70 in 375H&H and a M70 in 375 Ruger could anyone demonstrate a measurable cycling speed difference? It would make for an interesting experiment.
Dead men don’t talk
But there are many tales from hunters like Karamojo Bell who were adamant that shorter cartridges made a difference .