The 338 Federal with 210 grain TSX is not what I would call a fast round, yet check out the damage it did to this Zebra's heart
Exit in hide
Shot was about 100 plus or minus yards....
That is quite impressive.
Just to be clear, it's not my opinion that hyper velocity is a requirement. Only that it would be ridiculous to believe that your load would somehow be even more destructive had it been going 500 fps slower, due to longer "time on target".