Does hardness verify lead alloy's chemistry?

[Naphtali]

I've acquired scrap lead and scrap lead that has been cast into one-pound ingots from several different people. When buying unknown alloy mixtures, is hardness a valid test for chemistry? That is,

1. Will it make any significant difference in accuracy, point of impact, or other were materially different lead mixtures -- at same hardness -- used in cast bullets from same mold for same revolver?

2. Are there [relatively] common different lead mixtures that air cool to same hardness range when cast into one-pound billets?

3. Am I concerned about a non-issue?

[Leftoverdj]

Hardness does not tell much about the chemistry. I have no idea of whether there would be an accuracy difference between lead alloys of the same hardness, but suspect it would be minor, at most. A hardness of, say 12 bnh, can be attained by adding to lead tin, antimony, or a combination.

Most of us make all this a non issue by throwing whatever is at hand into a big pot and turning it all into one homogeneous batch.

[leftiye]

Nope, it don't. My guess however is that alloys of similar hardness will shoot similarly. This except in cases where maybe there is a dearth of tin, or too much antimony (boolits shrink less when cooling). These characteristics usually produce different hardnesses and weights though anyway. I treat alloys of the same hardness as if they were the same alloy.

[243winxb]

Does hardness verify lead alloy's chemistry? No. 1.significant difference- For air cooled, 2% tin along with the antimony is needed when you get above 900fps so you dont lead the barrel. 2. The chart shows hardness for different alloys. 3. Only an issue if your barrel leads or bullet dont fill out when casting. I work in small batches, so if some scrap is bad, i dont ruin 100lbs of alloy. Peope have given me good and bad alloys. When you start casting, how it pours into the mould tell you a lot. Slow and thick is zinc/copper. Click for larger photo. http://i338.photobucket.com/albums/n420/joe1944usa/th_Alloy_20090610_1.jpg (http://i338.photobucket.com/albums/n420/joe1944usa/Alloy_20090610_1.jpg)

[Shiloh]

It is an indicator only, not conclusive at all

Shiloh

[sheepdog]

I've acquired scrap lead and scrap lead that has been cast into one-pound billets from several different people. When buying unknown alloy mixtures, is hardness a valid test for chemistry? That is,

1. Will it make any significant difference in accuracy, point of impact, or other were materially different lead mixtures -- at same hardness -- used in cast bullets from same mold for same revolver?

2. Are there [relatively] common different lead mixtures that air cool to same hardness range when cast into one-pound billets?

3. Am I concerned about a non-issue?


1. Yes. Aluminum is heavier that lead but harder. The mass and shape of the object are more important than its hardeness. If you got zinc in your lead will make it harder and lighter for example.

2. Yes but not by much I would think. Think about Stick on WW vs chilled shot. Wildly different hardnesses if water colded for example but the % of the recipe is only very slightly different. Unless testing the extermes of the scale a hardness testing will likely tell you what you don't have.

3. In pistols, maybe. In rifles its a major issue. You want consistency from batch to batch. If you're that worried mix you mystery metal in big batches of WW on a 1:20 ratio to water the mix down and get closer to a known alloy. If you think you got a batch of hard or soft stuff than test it and use it for extreme applications such as high velocity rifle or soft slow wadcutters.

[masscaster]

My suggestion is with any "Unknown" alloy already in ingot form is to smelt it back down, perhaps at 2-3 ingots at a time to see what impurities are in it. Arsenic, Zinc, and a few other metals besides Tin could be present in abundance. Until you melt it there's really no way to tell besides a useless chemical test to know what you've acquired.
There's nothing worse than taking unknown alloys and dumping into your lead pot, to find out afterwards it's BAD!! And the fact of whether or not all of the ingots and scrap pcs. are of the same Lead type/Alloy. Casting away fine and adding a lb or 2 of Bad Alloy isn't worth it in my opinion. A constent & clean Alloy is part of the casting procedure. Know what your using FIRST.
Jeff @ forefather's Casting

[243winxb]

Some scrap given to me many years ago as Bearings, seemedl like it would be great for casting bullet. I could not get a good bullet even at maximum pot temeratures. It had to be some kind of Babbitt metal i guess. Sure glad i didn't mix it with good alloy. If you have a very high content of antimony, the test bullets should be large in diameter and very hard, but you can still only guess what the mix contains. http://en.wikipedia.org/wiki/Babbitt_metal