Heat treating cast bullets

lyman54

lyman54

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I've started to make my own 308 loads with WW's. They look ok and have loaded 50 rounds with 22grs of H4895. This gives a bit over 1600 FPS so should be ok as far as leading goes. Has anyone tried the oven method of hardening and what were the results. I would like to get the Lee tool to test them, but it will have to wait a bit. Thanks for any info. :stirthepot2:
 
when you cast do you air cool, or water drop? that will help a decent amount for hard bullets. though i imagine you know that already.
 
Heat treating has no significant effect on the hardness of lead. Water dropping with the presence of antimony and arsenic hardens the exterior (pure lead or lead/tin annoys are unaffected by water quenching). I'm not completely sure but heat treating after the fact may actually soften water quenched lead/tin/antimony/arsenic alloys.

Different metals with different properties are effected in different ways by heat treating. Steels are usually hardened by heat treatment but brass for example is actually softened (it can only easily be hardened by alloying or work hardening). Quenching hot steel hardens it but quenching hot brass is no different than allowing it to air cool.
 
Water quenching will harden bullets 2-3 BHN is what I found. If your bullets are sized right and have gas checks then ww should work perfectly Ok at that velocity. Going past about BHN 20 doesn't seem to help and can even cause more leading. Also, I find that faster powders definitely increase leading.

Water quenching does harden the bullets a few BHN, but they soften up again over time - after a couple months they are right where they would have been if you air cool. So if you don't shoot them within a month or two, then water quenching won't actually do you much good.
 
The info is much appreciated. I did drop the 1st batch of 50 in water, although I have heard about it being a short term fix. I will go on the link that SKS50 provided and see what's on there. I suppose for just punching holes in paper they will suffice as they are but I'm trying to learn more about it. It sure will save money on bullets and powder, not to mention the brass no doubt will last longer. Thanks everyone.
 
Ok, so I followed the link that SKS50 provided and would recommend reading it. Parts of it a little over my head, ok maybe more than a little but I kinda skimmed through it. In any case a tester would be a good idea.
 
jethunter said:
Water quenching will harden bullets 2-3 BHN is what I found. If your bullets are sized right and have gas checks then ww should work perfectly Ok at that velocity. Going past about BHN 20 doesn't seem to help and can even cause more leading. Also, I find that faster powders definitely increase leading.

Water quenching does harden the bullets a few BHN, but they soften up again over time - after a couple months they are right where they would have been if you air cool. So if you don't shoot them within a month or two, then water quenching won't actually do you much good.
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Its all true. Useing air cool W-W bullets at that speed (1600fps) that are at least .001" oversize, have gas check and good lube should be sufficient in your rifle for paper punching. For hunting and greater speed you need to add 20%-25% of linotype and rise hardness from 10-11 BHN to 15 BHN or so. That's the way I am doing it with my Marlin 336 in 35 Rem with great accuracy, no leading and exeptional terminal performance.
 
There is some variation in hardness of ww. I melt smaller batches of WW, about 10 pounds at a time and test the ingots after - I find BHN ranges from 10 to 14. I use the harder ingots for rifle bullets. A 13-14 BHN ww alloy with 3% tin added tests at 15-16 BHN and has worked well for me in 9.3 and 30 calber. Adding the tin makes the bullets fill out better too.

In my experience the most important factor to prevent leading in order of importance are:
1. bullet diameter at least .001"-.002" larger than the barrel groove diameter
2. bullet hardness
3. powder selectionn

I've been shooting a gas checked 280 gr .368" boolit at 1700 fps with that alloy and haven't had leading problems using IMR4895 powder - but it did lead up a bit using IMR4064 and was worse IMR 4198. Faster burining powders seem to cause more leading problems.

I definitely recommend getting a hardness tester - it takes out some of the guess work.
 
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