Thank so everyone, it is a 9mm and the recoil spring per the smith is stock at 23#. Today the failures moved to various rounds in the magazine rather than the first. The smith does suspect the firing pin safety plunger...it appears to be much like a firing pin block in striker fired pistols. I am also just to eliminate it as a cause, moving my thumb to riding atop the safety to eliminate operator error putting just enough upward pressure on the lever to slow the rate of hammer drop.