I’ve used candles, kerosene candles and a propane torch, standing in water and twirling on a finish nail held with pliers. My preferred method these days is the torch with low flame as it works better for me than the others, particularly with larger caliber/cases. I drop them in water only because I don’t care to handle them when the case head starts getting hot. Only time I screwed up was the first time; .22 HP brass standing in water...got them too hot and it took a couple of fire/load cycles before they started behaving.
I have brass for a variety of cartridges that have been fired 15-30 times and are still in good shape.
