I always had trouble with S&W, RH and Bisley. I can never get the same feel or grip. I get along fine with a SA and Pachmeyer grips. The Uncle Mikes on my BFR's feel the same.
The S&W 29 was the worst, just setting the gun down between groups would move the whole group 10". I had 5 or 6 over the years, all shot tight but moved down the road. I would center all 5 chickens at IHMSA and miss the next 5. Consider 10" at 50 was 40" at 200. To shoot a 20 was tough.
Gun fit counts a lot. With my SBH I could shift on the grip as distance changed without missing.
Now a SRH just needs a firm hold.