The short-stroking advice is probably correct, especially if you have modified or chaged the rebound slide spring to a lighter spring.

Another possibility is the stop is catching, or not being pulled down properly and in time by the trigger hook.......or it is coming back up too fast. (skipping)

If there is inadequate material on the trigger hook or the stop bevel due to wear or improper intervention or fitting, the stop can be "late", that is, it's not being pulled down out of the stop slot in the cylinder soon enough, and locks the action.

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Ret. LE, FA Instr, S&W Armorer