A .357 at the minimum.Cane Corsos are tough and incredibly quick,so you better shoot straight and fast.
Personally,I’d go with a 12 gauge and OO buck.
A .32 acp in the boiler room will take em down just fine. All day long. A .38 or 9mm will do it magnificently.
And with a money back guarantee for almost instantly if its a contact shot. Their “toughness” is simply a part of the trite persona and culture of people who love to imagine how tough their dogs are, and by extension, them too.