I guess I wasn't listening as closely as Mel was on this one as I didn't catch the humor (I usually do).  However, I did like the story and the conclusion - I had figured out the plot device about the bullets, but not the powder.  CBS had Mason Adams play a "tough guy" in several episodes, but I agree that if you saw him (or his picture) you wouldn't think of him in such a role (at least on screen).  Overall it was an enjoyable episode for me.