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Beartooth Regular
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Discussion Starter #1
Hello All,

Here's a post I made on another forum and thought it would be of interest to fellow casters.

Picked up a slightly used Toaster Oven at a tag sale recently with the idea I could use it for heat treating bullets.

Took a couple dozen 358 pistol bullets cast from WW's and placed them on the aluminum pan that came with it. Cranked it up all the way and reached a temp of 460 degrees by the oven thermometer I placed on the tray. I didn't get into the slumping adjustment routine but just cooked them for 35-40 minutes and immediately dumped them into a bucket of cold water.

About 18 hrs later, they measured .092 on the Gussy tester +- .001 on either side of that allowing for the operator also. Not sure of the exact BHN number on this but that's pretty consistant hardness. I'll call it at 24 maybe. Really neat little tester.

By contrast my water dropped bullets are all over the map from .075 to .092 on the tester. Which was a bit surprising as I had a good rhythm going with casting. Could be a factor in accuracy also.

Regards,

:cool:
 

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Beartooth Regular
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1,116 Posts
Very interesting experiment. How many bullets did you do at one time? I wonder if having them closely packed would affect the heat treating process?
 

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Beartooth Regular
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1,177 Posts
Discussion Starter #3
Hello Bill,

I don't think so, had about 25 in there just for the first try. I believe the quantity together would have no affect.

You're actually supposed to try a bullet or two and raise the temp until they slump, then back off about 15 degrees. WW's can be as high as 480 degrees or more before they do. Couldn't get that high with this oven, so decided to try the max to see what happens. After testing a few more bullets, I'd say they are about 24-25 BHN. Still good for hunting. I could probably get over 30 BHN with the slumping adjustment. However, by then they would probably be too brittle even for a low antimony alloy. They'll probably age soften a bit anyway so end up at 22 in a year.

I'm going to either make a mesh tray out of wire or get an old large coffee strainer out of a coffee pot to put the bullets in for heating. This way I'll just dunk them after heating as they are quite soft when they are first quenched and can be damaged easily until they harden.

Later, you can even draw or anneal them down to a softer hardness by heating to say 190 degrees and vary the amount of time they are heated, then shut off the oven and let it cool slowly with the bullets in it. Modulate the time "cooked" to arrive at different hardness.

This is from a WW alloy that runs about 11-12 BHN normally. Very good hardening ability.

The water drop routine was the eye-opener too. Extremely varied hardnesses.

There is also the argument for and against sizing before heat treating also.

I just got the tester from a guy over on the cast bullet forum. It was designed by him and he had a number of them made at a machine shop for us who were interested. Quite reasonable and well made. Nowhere near the cost of one of those Saeco Testers either. Very handy to know what your actual hardness is running and it's consistency also.


Regards,

:cool:

(Edited by Contender at 11:11 am on May 28, 2001)
 
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