The Super Blackhawk (Dragoon) frame beats up the middle finger knuckle too. Bigger grips may help. Or gorilla hands.
Anybody else here remember that's why Skeeter Skelton among others always swapped out his X-RED framed Blackhawks for the older original style X, that so resembled the Colt Navy grip frame? Same reason. The original style couldn't get a run at your finger like the later 'REDesigned' so-called 'improved' style could.
One of the few design mistakes that WBRuger made, in the course of his life. And of course, even though it was pointed out to him over and over, he never changed it, stubborn as he was.