Only 75 mph for a Bob Feller fastball? Not very accurate if that’s what he was throwing one that day:
From wikipedia:
…when asked if he threw harder than any other pitcher ever, responded that at the end of his career players who had batted against him and also against Nolan Ryan had said Feller threw harder than Ryan. If that was the case, Feller threw over 100 mph. Although there is footage of Feller being clocked by army ordinance equipment (used to measure artillery shell velocity) and hitting 98.6. However, this took place in the later years of his career, and the machine used, like most of the machines at the time, measured the speed of the ball as it crossed the plate whereas now the speed is measured as it leaves the pitcher’s hand.