In the Jan 2019 Rifle issue, they included a copy of the first Rifle issue in 1969. I found an article by Alberto de Castro that made some sense to me. He proposed a simplified alternative to the Kinetic Energy formula (KE=1/2mv(squared), using Potence=Weight times Velocity. Using a 300gr 44mag load at 1100fps, we get a potence of 330,000. Using my preferred 45 Colt load of a 285gr at 1050, we get 299,250. Love to hear your thoughts.