A friend cleans his brass in a vibratory case cleaner, one of the benefits of their being polished is that he can see the annealing line better as it moves down the case, to just below the shoulder.
He sets up his torch so that it is secure, and uses one of the Hornady annealing setups. Because timing is half second (or more) critical) for the type of annealing that he (and I) want (not fully softened, some spring left, but more uniform) I suggested that he purchase an inexpensive battery powered audible metronome, from a music store. Set on 60 it gives an audible one beat per second. Using this in conjunction with the Templaq, he soon figured out that with the flame inner tip touching the center of a case neck, as it is spun by his cordless screwdriver, case in the Hornady holder, how many seconds it was taking. He also could see where the annealing line came out, after a few hundred repetitions, with the aid of the metronome, he now has the timing down so that he can simply use the progress of the annealing line to time his process. To stop the process, he tilts the holder so that the case is moved out of the flame, and falls into a bucket of water. I don't think that the water is needed, but it does no harm.
From all of this he has much more consistent seating feel, and more dependable accuracy from his .223 and .22-250 varmint rifles. This is probably the least expensive way to proceed. If you are using larger cases, you may have to improvise a holder. If you decide to do this. Let me know how it turns out for you. Good luck.
