Minimal (or optimal penetration).

PH Herve Houdebine prior to going to the blind. 460 Weatherby and a cut-barrelled shotgun. The cut-off shotgun is the recipe he got from JM Latrive, PH in Tanzania.
His leather jacket was in the backpack.
I'd have loved to have my Beretta every day 12 gauge.

IMO a bullet would just wheeze through the cat that could keep going, as a lead column would push and roll the cat anyway.
When in Alaska, the PH was using a drilling, as he experienced a couple of charges from brown bears and told me that the 12 gauge would stop and flat a brownie any time though temporarily.
After 12 gauge is a 728 calibre.
home made 12 g in Bosnia war