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View Full Version : Annealing(Softening) boolits



rays308
06-26-2011, 11:19 PM
I have some 311332s from wheel weights that were heat treated and are breaking off at the collection groove at the base of the bore riding portion.

They were heat treated at 425deg for 1hr. If I put them back in the oven at 350 for an hour and let them cool, will they regain there tensil strentgh and loose the brittleness?

imashooter2
06-26-2011, 11:41 PM
I've gotten good results by heating in a toaster oven to ~450 degrees F and then turning off the oven and letting them cool inside it.

Defcon-One
06-27-2011, 05:28 PM
Why 350 degrees? I'm not sure that you can undo the heat treating half way, which I assume is the reason for the lower temp.

I'd put them back in at 425 degrees, like the first time, then let them cool down slowly like they just came out of the mold, no water quench.

I think that should soften them down to normal unquenched wheel weight hardness and strength. I'm wondering how much Antimony you really have to be that brittle. Adding Tin helps some with that too, but it is a bit late for that advice.

sqlbullet
06-27-2011, 07:30 PM
350 for one hour and cool in place will work fine. And it will save you a few cents.