slow burning powders
I've always had good luck with slow burning powders; 2400, H110, Accurate #9, Blue Dot, or WW296.
You may want to wear a shooting glove and attach a lanyard so you don't have to look for your derringer.
To the best of my knowledge (and I've worked in numerous gun shops as well as owned a number of S&W's over the years) neither the 586 or 686 was called the "Combat Masterpiece". As far as I can tell only the 15 and 67 were called by that name
In spite of the larger and somewhwat heavier N frame I would still probably choose it over the L frame. I had a Model 28 with 4" bbl and currently own a 586 with a 6" bbl and while I like the longer sight radius and red ramp on the 586 the 28 was my favorite carry gun. Guess that's why the...