Something is really wrong with that 686. Mine has shot 500 plus rounds throughout an afternoon of family shooting with the reloads I mentioned and with some factory 38 and 357 loads.
It looked like a 586 it was so dirty but never once stopped working.
Sure hope you can get it sorted out. I would really like to get a new S&W Classic 25 but not so sure about taking the chance on it especially what it’s going to cost me.