Ballastics04,
I come down differently on Firearm size on critter,
First, the is no such thing as too dead.
Secondly it is all about bullet quality and integrity.
I never back off from using my 300win mag for deer, but then I use bullets with high integrity.
On my first cast bullet deer, I would need to agree if that was as far as I'd gone.
The 355gr WFN cast at 2300fps was nearly as bad as the results I've seen from the the 45/70 gummy nose.
The difference was that with the gummy nose, there was a huge amount of damage and with the WFN cast bullet, the meat was not minced, it was just gone.
However, with my current cast bullet, a 465gr WFN at 1600fps, there is simply not the minced meat of the gummy nose or the huge hole as with the lighter faster cast bullet.
So back to choosing a bullet to fit the caliber, velocity and critter.
Crusty Deary Ol'Coot