JPH45,
I did not know that I was promoting "pure balderdash" as you put it. I simply stated what has worked for the NRA Techical Advisor and no less an authority than the Lyman Cast Bullet Handbook, and most every maker of bullet molds and casting equipment. We have to assume that they know a bit more about bullet casting that most of us will ever learn.
John
Sorry, didn't mean to leave anyone feeling blasted....My bad, not too good with words sometimes. I almost typed "sounds like it was read from a Lyman manual", perhaps it is good thing I didn't.
To assume that that just because someone is selling something, that makes them an expert is bad thinking at best. Fact of the matter is that Lyman refers folks to the listed site, so I think the folks there may know more than the average bunch of folks on a website.
As to metals seperation, lead and tin form a true solution, this means that whatever amount the lead will take (22% or so by weight) makes a molecular bond with the lead, that is waht makes it a true alloy, kind of like what happens when you add tin to copper....you get brass, a completely different alloy form the base metals. This bond can only be broken with heat and the presence of oxygen. Tin will oxidize out of the melt, but not at any rate that will alter the alloy significantly. You can't get those kinds of temperature in your melting pot.
Antimony is a different animal altogether. Antimony does not alloy with lead, it will with tin. In a picture of the molecular structure of a lead/antimony mix, the antimony forms long tendrils that encapsulate the lead molecules. This is why it takes two weeks for WW to reach its mature hardness, the antimony is still growing. It is also why we are able to heat treat antimony alloys in the presence of arsenic. Arsenic alone will harden lead, but in combination with antimony, through rapid cooling (such as dropping the just cast bullet in water) we are able to freeze the antimony in a molecular relationship with the lead that allows for harder bullets. But arsenic must be present in the alloy to heat treat, otherwise all you get is cold bullets.
So, lead and tin do not seperate, tin and antimony do not seperate. Lead and antimony do not alloy in the true sense. We do not flux to keep the metals in solution. If that were true then as soon as the metal were removed from the heat and flux source, they would seperate.....we couldn't make bullets, or any other alloys for that matter.
A conversation about lead/tin/antimony alloys with Bill Ferguson of
www.theantimonyman.com will go far in helping to see how these alloys really work together.
Lyman states plainly that the mechanism that makes fluxing work is unknown, that is flatly false. Fluxing works by providing a carbon rich environmet that "steals" the oxidized metal back from the oxygen. The metal prefers the carbon over oxygen in other words.
Over the years lots of misinformation and wives tales has been propogated in the firearms industry and press, especially about cast bullets, Lyman and the NRA amoung the offenders. It is why conversations like this take place. Simple obsevation of the melt will reveal the formation of oxides. That does not mean that an untrained metalurgist will draw the right conclusions about what is being seen. And if the right conclusions aren't drawn.......And so here we are today, still working with bad information that is at least 100 years old, probably more so.
It was my intent to call into question the information presented, it is at best incomplete. It was not my intent to leave anyone feeling belittled or run roughshod over. My apologies.
..........Somewhere in this I would like to add that the tin oxidizes first because it is lighter.....on the periodical chart. Similar to why we galvanize steel, it will sacrifice first. It is a result of things at the atomic level. If we don't realize that what is occuring in the melt is really happening at the atomic level, then what we see there will always be a mystery to us.
Also, join the Cast Bullet Association
(Edited for spelling and link repair and added CBA)