Trying to discount me is what that question is meant to do. I will not retreat. I am a teacher and my funds do not allow me to experience world travel. And dispatching bovine flesh is not big game, but still revealing as to what kills, as is dropping bison which would be a traditional big game animal. So I will endorse good hard-cast bullets at adequate velocities, as has been proven effective in my arena of life.
I know what I have seen used kills effectively and I know normally docile bovine can become very aggressive in a split-second. But killing is just killing and even Karamojo Bell, who killed over a thousand elephants with most falling to a 7x57 using a 175 grain FMJ bullet. In his writings he self-disclosed that some elephants mysteriously were unharmed after he had made a precise aimed shot, and he was lucky enough to survive some close calls to tell the tale when all did not go as planned.
So after about a thousand elephants taken, he still had some things happen that surprised him. He theorized that the 7mm bullet would bend or deflect enough to miss the brain. So he upped his arsenal to a 318 Westley Richards and the problem was solved, in his mind. He even wrote later, after the .308 was made into a factory round, that a .308 with 240 grain FMJ bullets running about 2300 fps, would be his new choice for braining elephants.
And domestic fenced in bulls have killed unarmed men working with them, as an uncle of John Ross lost his life to a domestic bull for example. This is why John Ross eventually made a special run of 5-inch barreled 500 S&W X-frame revolvers with no muzzle-brake or ports. His belief in having a carry-piece for protection that would have saved his uncle's life was so great, that he ordered a minimum run from Smith and Wesson made to his special requirements. I have spoken with him over the phone. He sales them, but he may have run out by now.
I digress though. Killing provides experience, but it is not the only requirement for validity for sharing on this site.