IIRC, Brownells sells S&W hands that are thicker than normal and should solve the problem described. Peening the hand was common with the old Colt DA revolvers because the second level of the hand acted to bring the cylinder into full lockup by pushing directly on the ratchet tooth. But in an S&W the hand moves the cylinder and then moves up PAST the ratchet tooth so peening the hand won't help much if at all.
Fitting and oversized hand is not something the average person should try doing as this a job left best to a good S&W mechanic. I know a lot a gunsmiths who will not even attempt this job and send them out the back door for this work. To fit up a new hand can require opening the hand window, shaping or filing the hand tip correctly and fitting the hand to the ratchets for correct timing. Keep in mind most of the time one or two ratchets may be higher or lower than the others so the hand tip must be fitted correctly to adjust for this. The hand window and hand thickness must be close yet not so tight as to interfere — a job for a surface grinder really. It is possible to bend the hand tip to adjust for some timing issues but again this can lead to big problems if not done correctly. So I stand with the suggestion that just because you can buy an oversized hand don't think this is anywhere close to a drop-in fix