We know little about firearms, but we've read that single-action arms have a longer and smoother trigger pull than double-action arms, which are reputed to be at least somewhat safer but perhaps less accurate. We're sure one of our readers could clarify this easily, but we won't even try.
Returning to checkers: regular contributors Lloyd and Josh Gordon of Toronto sent in this position from one of their nightly games, and it's a position that is surely not safe for the Black forces, if White engages in accurate play.
It's not hard at all, and the title of today's column gives you a huge hint. So take a "shot" at it and after you've solved it, pull your mouse trigger on Read More to check your solution.
21-17 13x22 15-11 8x15 18x2 6-9 2-7---A 3x10 27-24 20x27 31x6 White Wins.
A---27-24 20x27 31x15 also wins with at two-for-one.
The two-for-two sets up a winning three-for-two, hence the "double action."