Who had the most powerful right hand among light-heavyweights?

Saad Muhammad IMO. He was so strong he could move a guy with glancing blows.

 

As or more important than the power of Moore's punch was its effectiveness. He had the smarts to be able to set up his opponents before delivering the coup de grâce. Having an open target made the punch more effective. He did this not only once, but many times. As most of you know, he stopped 132 opponents (according to BoxRec), more than any pro fighter in history, certainly a record that will endure for all time unless the sport of boxing changes dramatically from what is right now. The right hand was his money punch. And he didn't just throw it willy nilly. He was always working to set it up.