Sorry for the poor quality scan & the delay in posting this.
Pay particular attention to the trigger rebound slide section. The S&W trigger rebound spring is usually too heavy & the trigger rebound slide usually does not travel smoothly in the frame & it is rough where it rubs back & forth on its retaining pin. That is USUALLY the main part of the problem with a rough & too heavy DA pull.
And also the DA fly on the hammer & where the trigger rides on it through the pull.
Maybe...I'll pop a S&W apart & point those areas out in some photos. That might help...lok for that in a couple/few days. It's a busy time for me right now. I'll post them as soon as I'm able to.
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