I shot one in .45 Colt, back in the 70's. I was doing a lot of .44 mag shooting at the time, and elected to only fire the 2 shots in .45 Colt. Recoil wasn't that hard, but the flip made the hammer dig into the web of my right hand. That was the nasty part.
Having only the trigger finger and middle finger holding on, was the problem.
Shooting 300gr. Truncated cone Bullet Barn cast with 20.0gr. W296 with the short round rubber grips on the 4" M29 actually stung the palm. Hell of a slap. with those shorty grips, 2 fingers plus the trigger finger, with the little finger curled under the grip was the problem.
With normal Pachmeirs or wooden magnum grips, those loads are quite manageable.
12 rounds rapid fire would make my hand bleed a bit, though. It would split a bit in the web. Need toughening up, I guess.