Answer #A - The same SD loads as in your 4 inch revolvers , unless your have physical injuries / infirmities that mandate minimum recoil.
Answer #B - * I'm * convinced to use factory loads for delibert SD , and use equivalent reloads for practice and field shooting . The number of instances where it became an issue ( primarily in analysis of distances where rounds fired ) is significantly more than zero , just in cases where Mas was an expert witness . Even if defendants usually prevailed , no need to cause unnecessary hurdles for your defense . And particularly in the modern era when every caliber vaguely suitable for deliberate SD has plentitude of good SD options that can't be materially improved with cannister powders within pressure specs .
But y'all do what you're gonna do , and I'll save my internet efforts for important issues like 115 vs 147 , or Appendix vs Pancakes .