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mrhunterken
10-15-2016, 08:03 PM
Gentlemen, I have about 300 lbs. of a lead alloy that I was forming into ingots today, I also have some 30/1 alloy which was ordered from BACO. The alloy I have seems much harder, and when dumping my ingot mould, one of the lead blocks broke in half (still very hot)I noticed internally the lead seems to have a crystalline appearance to it. I have shot some of it and it seems to shoot well, when casting, the bullets mostly drop on the heavy side, something in the order of 540 grs. from a 525 gr. mould. Is this alloy overly hard, I have no way of testing to see how hard it actually is. My thumbnail almost glides over it. I'm just really curious about the crystalline appearance. Any thoughts, should I shoot it as is or try to soften it up.
Dusty Bannister
10-15-2016, 09:00 PM
If you do not let the lead harden long enough, it will still be mushy when you dump the ingot mold. I would say the reaction is normal for a lead mix. If you have concerns about the hardness, cast a flat nosed bullet from the same mold and from each lot of metal. If they have been done at nearly the same time, you can then compress them base to base in a flat faced vise and the softer lead will result is a shorter bullet. If they are the same after squeezing in a vise, then they are close enough to the same to be of no concern.
mrhunterken
10-16-2016, 10:21 AM
Thanks Dusty, that's a good idea, I can use pure lead as a control. I'm curious about the crystalline appearance, I have never seen that before. Of course I don't go around trying to rip apart lead bars, and I'm no chemist, I've looked at lead that has been sheared, and never saw a sample that appeared crystalline before.
vintagesportsman
10-16-2016, 11:43 AM
3rd edition of the Lyman Cast Bullet handbook has an article about the metallurgy of "High Temp" casting. Sounds like the temp. was over 800 on your melt and caused a crystallizing of the lead.
Retumbo
10-16-2016, 12:34 PM
Lead, tin, antimony all have crystaline structures.
Retumbo
10-16-2016, 12:37 PM
Galena...lead

https://en.m.wikipedia.org/wiki/Galena
runfiverun
10-16-2016, 06:26 PM
I'd say you got some ww alloy.