Ideal Bullet Metal

Two things: 1) I once read a technical report stating that the ideal bullet metal was an alloy 80% Pb, 10% Sn, 7% Sb, and 3% Cu. I lost track of the reference. Does anybody know what reference cited this statement?
2) How would you get that much Cu to stay in suspension in the alloy at around 700 F. The 10% Sn should hold about 1% Cu saturation in the mix, but what holds up the other 2%?
Just questions from another amateur alchemist.
Comment: I have been attempting to use a Rotometal approximation to this ideal solution. Using 5.25lbs pure Pb, 1 lb super tough Babbitt for the infused Cu and Sn and 1.6 lbs of super hard nuggets. Ends up 81%Pb, 11% Sn, 7% Sb, and 1% Cu. The BHN is around 18+ water drop. The gain is super fine and you can hammer it flat and stays together. Once PC'd it behaves like an FMJ, tough and hard. So what more would the extra Cu do if you could make it?

while I can't answer your questions, I would assume that a lead alloy with 7% Sb that was WD would be considerably harder than 18?

Also, for searching reference, when you say "the ideal bullet metal"
I am curious if you are using ideal as a adjective or noun?

"Ideal" (as in the noun) had several alloys. Per Whelen circa 1909 #1 alloy was 80% Pb, 10% Cu, 5% Sb, 5% Sn. #2 alloy was 87 % Pb, 8% Sb and 7% Sn but I've seen a couple other formulas that were close but not quite the same. The #2 alloy was changed in the late 40s or early 50s to 90% Pb, 5% Sb and 5% Sn. #1 alloy was dropped prior to WWII in the thirties(?).

Thanks Larry,
You saved me some searching...I figured the Ideal company had a specified alloy/alloys.

Phantom - combines with Sb (& Sn to an extent), works fine. I've gone to 2% WD (>36 BHN) 6% appears to be max for toughness. Sb must be higher than Cu. I haven't used tin in anything for a long time.

"Ideal" (as an adjective) bullet alloy depends on the application, and perhaps is subjective in any case no?

Starting with the BHN 8.6+.29*10+.92*7 = 17.94 is there something wrong here? Plus the effects of water drop. Hardness is not a desirable here as toughness, which Cu is supposed to provide by tightening the grain structure.

Ideal meaning as in the right stuff

Popper so the Sb supports Cu in solution like the Sn does in the mix so that's where the support comes from for the extra Cu. Don't have a lot of state variable phase relationship tables and charts. Have monster CRC properties manual but when you get to quartenary alloys nothing listed.

Larry the report was an old army tech manual

Popper -- Rotometal 1 lb babbitt super tough is 84% Sn, 8% Sb, and 8% Cu. I use it for the Cu. The Sn-Cu tables shows about a 10 to 1 solubility at temperature. But if the Sb is carrying Cu at even higher solubility than where is the product that has Sb and Cu. Hopefully cheaper than the Babbitt.

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Originally Posted by Phantom30

........Larry the report was an old army tech manual

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No doubt as a lot of cast bullets were used by military shooters. Earliest I read of Ideal's (the mould company name) #1 alloy was in Lt. Townsend Whelen's book Suggestions To Military Riflemen (1909) originally published in 1909.

Sb & Cu form a molecule, Sn & Cu do also BUT it is primarily a transitional molecule that doesn't exist to any amount in the solid. Cu also (solubility part) atoms drop into 'holes' in the Pb lattice and form 'speed bumps' that add strength.
Supertough and COWW (25:1) gives 3%Sb,3%Sn, 0.3%Cu.
I added 2%Cu to my 4%Sb alloy, heat treated it dents an ingot of superhard BHN>36. Shoots fine. Have a few left I might get a chance to shoot at steel and try to recover.

Popper: This picture shows the toughness of the 81-11-7-1 alloy. Bama PC'd one of my bullets and then hammered it flat, it still hung together and shows fine grain. I don't really want super hard results. Bama's bore rider tools and processes require a lot of sizing pre and post PC. So Hardness makes the process more difficult without using a swaging press. Bama also discovered that the cable pulling lubricant Yellow 77 works as an excellent sizing lubricate. It washes off in a colander with water and does effect follow on application of PC.
I am trying to use this stuff in an auto loader AR so you don't have the liberty of being able to hammer the bolt back if one sticks so sizing is important. I had a barrel maker make a sizing check tool for the bore rider and chambered round, so I had confidence in the results before sticking them in the barrel. The bottom line is doing what it takes to maintain concentricity and accuracy in high speed long range applications.

I use super hard (IIRC) that doesn't have the tin or Cu, add Zn to replace with Cu. Hard & tough is easy, been trying for soft - not much luck with it so far in 1:10 308W lr308 full power. Pretty much convinced it takes a much slower powder than 4895.

I bet those alloys cast beautiful bullets but they sound awfully hard for my uses. I prefer something in the 96-2-2 or even 94-3-3 range. I get great looking and performing pistol bullets from straight wheel weights at something like 96-2.5-0.5.

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Originally Posted by lightman

I bet those alloys cast beautiful bullets but they sound awfully hard for my uses. I prefer something in the 96-2-2 or even 94-3-3 range. I get great looking and performing pistol bullets from straight wheel weights at something like 96-2.5-0.5.

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Yeah, I guess I have come to the conclusion that unless you are doing something vey high powered the alloy you use for pistol boolits isn't that critical. Something from range scrap to ACCOWWs plus a bit of tin works very well. Where I need to do some experimenting is rifle boolits, especially for something high powered like 30-06. I have been using 3% tin and 3% antimony and it seems to work well up to 1900-2000 FPS. I have thought about going harder to try for accuracy at higher speeds, but I don't want to end up with a very hard boolit that is going very fast and merely pokes a hole in a critter and keeps goung (or worse, hits a bone and explodes). So I need to mess around with home rolled Lyman #2 with 5% tin and antimony and see if that makes anything different.

With such soft alloys looking like they do very well in most non-magnum and many magnum applications, I cannot help but wonder at the popularity of 18 BHN boolits as sold by Missouri (think they use 6% antimony, 2% tin). Do you get anything from using such a hard, high antimony alloy?

Popper tried H4350. I am also trying to get this alloy to work in both Creedmoors 6mm (116gr 2970 fps 1:7 twist) and 6.5 (140gr 2700 fps 1:8 twist). Later has G1 BC estimated at .416 so that should be supersonic out pass 1,000 yards. Hitting anything gets right back to concentricity, consistency and variability imparted by slamming home over feed ramps and breech counter bores in an auto loader MSR.