Not sure if posting a link to another forum is allowed...you will find more info if you google candle annealingA candle flame isn't very hot. I'd be afraid of the annealing going too far down the case by the time the mouth gets annealed. If you haven't, I would suggest some Tempilac or similar to see what's actually going on with your cases over a candle. If you have and it worked well please post your technique to doing it.
I've repeatedly read that setting up annealing by color alone can not achieve proper results, this from highly experienced people who actually test what's going on. Those who've never done any temperature checking and hardness testing will tell you that color is all you need. If a case is under heated no harm done other than waste time & propane. If it's over heated it could be a big problem.
So, the thing is, someone else was wondering about this, bought the necessary Tempilaq stick and found out for themselves.I suspect that they're not getting hot enough to anneal, unless your fingers are made of Nomex. I don't recall the exact numbers but from what I've read a candle puts out somewhere around 800 and brass doesn't change 'till it hits around 700. Brass conducts heat pretty well so my guess is that the neck wouldn't hit annealing temp before your fingers would be burning.
I'm not bashing the method nor what you do with your idle time, just saying that it might not be doing anything for the brass. If you've used some kind of test method to confirm that the brass is annealing I'd love to know. If this simple process really works reliably I'll be lighting candles at TV time.
I've actually adjusted my thinking some on this as a result of recently re-reading Fred Barker's article on brass metallurgy and annealing (Precision Shooting, July 2006, p.p. 90-92). He points out something I hadn't known, which is that overdoing heat weakens brass so much that it actually encourages necks to split in just three or four subsequent reloadings. That is why people getting cases red in a torch flame often report having to redo it about that often to prevent splits. If you really get the temperature right you might go twenty reloads or more before splitting is a threat in medium power cartridges.
Barker refers to Fred Sinclair's doubts (Precision Shooting Reloading Handbook, 7th ed., p .10), that handloaders have adequate equipment to control annealing properly. Barker cites the same doubts expressed in the 47th Lyman Reloading Handbook (p. 51). However, he points out that a study of the metallurgy leads you to understand there are a couple of methods that will do the job without resorting to Tempilaq for a propane torch: stress-relieving in a candle flame or mild annealing in molten lead. He describes the methods in one long summary sentence (caps his, not mine):
" (1) LEAD POT METHOD: HEAT LEAD TO 725°F-750°F; DIP NECK INTO POWDERED GRAPHITE AND THEN—HOLDING BODY OF CASE IN FINGERTIPS—INTO MOLTEN LEAD: WHEN CASE BODY BECOMES TOO HOT TO HOLD SLAP CASE INTO WET TOWEL; OR
(2) CANDLE-FLAME METHOD: HOLD CASE BODY IN FINGERTIPS, PLACE CASE NECK IN FLAME AND TWIRL CASE BACK & FORTH UNTIL CASE BODY IS TOO HOT TO HOLD, THEN SLAP CASE INTO WET TOWEL; WIPE SOOT OFF NECK & SHOULDER WITH DRY PAPER TOWEL OR 0000 STEEL WOOL."
The graphite dip in the first instance is prevent the lead from soldering to the brass. Using pure lead with no tin in it will help prevent that. But to your original question, yes, the candle will do the job. The flame doesn't have high enough BTU output to easily take the brass above a safe stress-relieving temperature before thermal conductivity draws excess heat away from it.
A candle flame isn't very hot. I'd be afraid of the annealing going too far down the case by the time the mouth gets annealed. If you haven't, I would suggest some Tempilac or similar to see what's actually going on with your cases over a candle. If you have and it worked well please post your technique to doing it.
Some time ago, a fellow named John Barsness did an article in Handloader magazine, and he uses candles. A metallurgist friend of his developed the method, using tempilaq, so he knows the temperature is enough.
It goes like this: Get a candle like is sold for emergencies in almost any supermarket. Light it, hold the brass about halfway along the body, twirl it in the candle flame till it gets uncomfortable to hold, then drop it onto a wet towel, which helps with clean-up. Easy-peasy. He says it works fine. It seems to .
I have done 200 303 savage necks in one sitting while watching a few TV shows. Not so bad on the fingers at all. Keep in mind these are really long necked cartridges. When I did 223 Rem is was 3 times as fast.The candle method would be ok if you only had a few to anneal but doing 100"s would take a toll on your fingers I presume.