I've always used a drill and propane torch and decided to give the candle method a try. I needed to size 50 rounds of well used 223 into 222 Rem, with the candle method I was getting wrinkles and fold when moving the shoulder on about 50% or more cases. I went back to the torch and the ruined cases dropped significantly.
When annealing for case forming 9.3x72R to 6.5x58R Sauer sometimes I have to anneal two or three times before I can get the case formed.
9.3x72R right to 6.5x58R Sauer center.