commander faschisto wrote:Cool, thanks Hoot! I take it that one looks for the brownish color change in the brass as a guide for the proper temp being achieved (in the absence of TempLac)? Or...what, exactly?
Though I'm rarely at a loss for words, I hesitate to try and describe the "look". They go from normal brassy to dull brassy, to straw brown, to darker brown and shortly thereafter, blue. IMHO don't let them get to blue before removing the heat. You will wind up overshooting. The key is to not heat them directly on the mouth. It's thinner there and there is no brass on one side to wick away the heat since it's the end of the case and consequently the mouth will overheat before the temp line runs far enough down the case. The key is to heat at the mid point from how far you want it down the case to the mouth and let the heat migrate in both directions toward your stop line and the mouth. As the color nears the mouth, stop and let the heat migration
coast to a halt. So, if you wanted to anneal from the mouth to 1/2 inch below it, you would put the pencil sharp flame at the 1/4 to 1/3 inch point, while rotating the case around 1 revolution per second. Let it continue to spin while the heat line coasts to a halt and then drop it onto a cooling surface, or if you just absolutely have to, into a quenching bath. The small, precise, controllable flame is the key to not overshooting. If you use a dot of TempLac at the mouth, still heat about halfway between it and the furthest down point you want to go. We rarely seat bullets beyond a half inch into the case, that's why I used that example.
A good rule of thumb. Unless you're blessed with "Kung Fu Grip", try holding an empty case at the mouth, between your thumb and index finger. Try to squeeze it shut. You should not be able to permanently distort it. If after annealing one, you can do so, that would be an example of having gone too far with the heat and you are holding a ruined case. If I had a camcorder, with good color rendering, a video would be worth a thousand words. This is the process I use and it does change the hardness of necks. When I was necking up 25 WSSM to 30 WSSM, I would use this technique, throw in 13gr of Unique with a grits filler and a Styrofoam cup wall plug. They then fireformed to the new neck dimension. Out of the 200 I did, I lost one case and believe me, it could just as much been a kinked case from Winchester as my process' fault. Their QC on 25 WSSM brass ranged from good to 20% kinked right out of the bag.
Hoot