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rtracer13
08-11-2015, 11:38 AM
Received a box of cut and ground metal that was told was pure lead. Within 24 hours of melting and casting it into bars it reads BHN of between 7-8.
It seems much shinier than lead I've got previously though they were mixes so not sure if that is norm with pure lead. It is non-magnetic, and melted at approx. 720F. When pouring it seemed to harden and stick the my ladle much quicker than the mixed lead I poured before. Is this likely pure lead (that will need some mixing to bring up hardness) or some other similarly good casting metal or should I keep it out of my melting pot for my bullet mix?

146389

lobowolf761
08-11-2015, 11:50 AM
It might have some tin in it.

mdi
08-11-2015, 11:53 AM
BHN 7-8? Shiny? Prolly pretty dern close to pure. I would treat it as pure for my casting/alloying needs...:smile:

bangerjim
08-11-2015, 12:00 PM
Probably pure with a some Sn in there. Sn does not raise the hardness much. 2% will make VERY shiny castings yet not be much above 5 in hardness.

As always...............only an x-ray gun shoot will tell you for sure.

rtracer13
08-11-2015, 12:01 PM
Ok thanks! :D was worrying all over it, but the more I read about it figured it couldn't be bad for the casting unless it was zinc and my lyman thermometer was off a fair bit.

jcren
08-11-2015, 12:04 PM
As far as temp, pure lead actually has a much higher melting point than most boolit alloys

rtracer13
08-11-2015, 12:19 PM
Was mentioned by an experienced board member that it would be beneficial to show the original metal before melt, as well as back side of mold. Had photos of both the blocks and ground were given to me in that form the ground was said to be the shavings from when it was cut into chunks, and the chunks were left-over.
Here they are:
146396146397

bangerjim
08-11-2015, 12:24 PM
Zn is not shiny like that! It is duller and lighter than Pb. And melts at ~787°F. Sn imparts shine to Pb. Pure Pb can be shiny also depending on the temps and conditions you cast it at. But it will be soft.

bangerjim

Moonie
08-11-2015, 12:55 PM
There is a formula to determine a binary mix's contents. If it is just lead and tin you can use the formula to determine it using water displacement.

Moonie
08-11-2015, 12:58 PM
http://www.texas-mac.com/Measuring_and_Using_Specific_Gravities_of_Lead_All oys.html

sparky45
08-11-2015, 01:07 PM
ALL the pure I've melted into bars (source was Lead Pipe), has a purple sheen and BHN of 5-6

bangerjim
08-11-2015, 02:17 PM
ALL the pure I've melted into bars (source was Lead Pipe), has a purple sheen and BHN of 5-6

The color is because you melted it too hot. Does not hurt anything. Pure can be a whole bunch of hues.

Color means nothing if pure Pb. And since there is nothing in there to cook out, you can melt it at temps higher than needed. I have ingots of pure that are silver, gold, green, purple, and just about every combo in between. It is all in the melt temp and how fast they cool....seems like.

banger