Well, actually the military annealing specs center around controlled use of flame. I do think, though, that it is easier to control an induction heater with a timer to get consistent results. I've experimented with a couple of designs to get the efficiency up and will show how when I get more time.
Here's
the thread I was thinking of from late 2009. Unfortunately the movie link is broken now.
Also, I bought a couple of metal plates with pins for 223 and 308 cases years ago. You heat the plate to 700°F and just set case mouths over the hot pins for about 20 seconds each in a round robin. Worked OK as an alternative heat source, too.