Just started annealing some 243 WSSM brass, and i heard the 650 crayon was a good way to get it as precise with temp as possible. The problem is it's not really like a crayon, it's more like chalk, and it doesn't adhere to the case neck at all. What i did was just scrape a little off on the inside of the neck. This way it would stay on the inside while i spun it on a screwdriver on the point of the torch, and at about 5 seconds it melted and dissipated. Seemed to work pretty good.