anyone using salt bath for annealing brass?

I've been using a 60/40 % mix of potassium and sodium nitrate at roughly 700 F for a couple of years.  I have on old Lyman or Lee lead pot with an internal heating element.  I use a PID controller to hit the correct temperature.   

I use a pair of tongs to hold the case and dip it in the salt for maybe 5 to 10 seconds.  Not too deep. I then drop the case in a bowl of water which I keep far from the molten salt. 

It works great but the molten nitrates are somewhat dangerous.  If you get any water of organic material in the hot salt it will explode.  When that happens, according to what I've read, it can set fire to anything organic that it hits.  The nitrates are just like the potassium nitrate in black powder.  I don't think it is much different from playing with molten lead.

I've seen some salt pots that use a plate over the salt pot with holes that fit the case and a shelf under the lid to control the case immersion depth.   I haven't built one of those yet but it seems a good idea.  One could speed up the process if there were say three or four holes.

I also use the salt bath to blue small parts.  They come out really nice.   

Dave

Potassium nitrate is stump killer at garden shops. I'd check the label to be sure. It's easy to look up the melting temp. and doesn't really need the sodium nitrate in it to anneal brass. I've been around splatters and a bubble over of heat treating salts, a little carefulness is sound.

Here is a pretty good set of posts on the 6.5 Creedmore forum that show salt annealing.  The guy uses a 939 F (500 C) melt temp and 5 seconds immersion time.

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Dave