Now to address something that used to be true, but isn't any longer, at least with all the major brands of American primers I know of. Handling primers with your fingers has zero effect, because years ago manufacturers started sealing the priming compound with a water and oil-impervious coatiing. In fact you can soak 'em in water or even oil for several days, rub off the oil, and they'll still go bang. So no, there's no danger of turning a modern primer into a "dud" by handling it with your fingers.
John,
I'm glad you pointed that out. Early on when I'd have a rare FTF, I used to wonder if I had gotten a little case lube on the primer while handling it, but more recently I know that most, if not all, modern primers are sealed and in the one or two instances that I've had a FTF, it was either a faulty primer or something in my process had gone wrong.
