This is a very interesting read. I remember buying some bulk lead scrap from a lead foundry. It was lead "came" The leading used in lead windows. The .06% figure that 303 guy came up with is exactly the copper content in the window lead. Also .45% antimony. I shot a black bear with this alloy +3% tin added. The bullet retained 100% weight and expanded nicely, but I'd have expected that with or without the copper in the alloy. Velocity was only 1380 ft /sec. It'd be interesting to see if this copper containing alloy could help achieve higher velocities while remaining malleable, than alloys without it. Ron.D
Not to get off topic again, but to those who mentioned it, the lube you are using on the boolit will make a lot of difference in the ability of the boolit to withstand HV and not lead your barrel. I go to to 2700 fps regularly and have no problems with leading or accuracy.
I have wondered about the effects of Cu found in babbit alloys when it used to make boolits- I am reading and following this thread with great interest! Keep up the good work guys!
USMC 1980-1985
you guy's see post #56.
think about that for a bit.
low solubility and hardening.
it works for copper and zinc and other such stuff like silver too.
anything that does not add brittleness to the alloy will allow you to make a tougher stronger alloy
that will withstand higher pressures.
it will resist skidding in the bbl and still will allow the alloy to remain malleable when striking an object.
you guy's have seen the lamp cord that comes in copper on one side and silver on the other right?
well the silver side is tinned copper strands.
Usually, just the connection ends of cords. It's too expensive and time consuming to to put that into every cord. Tinning wires, and also the tracks on circuit boards, provide better connections, better heat resistance, more capacity for current, and resistance to corrosion in electrical circuits, IIRC.
My 225415 boolits that I have fired from near max 22 Hornet loads (around 2650 fps) were accurate, did not lead barrel and had the ability to penetrate 3/16 inch of a 3/8 mild steel plate. Alloy is around a 12 in hardness, IIRC. Of course, there is nothing left of the boolit, but the divot! Hardness is realitve when speed is added.
USMC 1980-1985
FYI- on lamp cords, there is one side that has ridges in the plastic running the outside length of the cord to indicate polarity (neutral side, IIRC).
Yep, seen that. Have also seen some DC-type wire that had dashes on one conductor, control cabinet wire I think.
I reread most of this thread, hoping we bump it enough 'til that antique-shootin' Kiwi gets his new alloys tested!
Also looks like Robroy is formulating one.
Now I'm wondering about the sheet lead I got, 'til now I thought all sheet lead was gonna make soft boolits
(was gonna use it for slugging bores).
Might have to evaluate it's usefulness after casting a few with JUST the sheet stuff.
Also if my stash turns out to be harder than I thought, I won't need to alloy the copper into it
(unless 303guy finds the ductility improvement formula),
and if what I have is pure copper I might just trade/sell it for primers or something.
Sagacious, testing copper with salt solution reminded me to test the suspect pewter item, I think you said
a little salt and citric acid in H2O would make hydrochloric, which would bubble on zinc?
As long as the swamp cooler is running it should be safe enough!
Just a quick add:
Someone on here was sellin' assayed ingots, I wonder about cost of commercial pure lead vs
cost of assaying some pipe or sheet lead?
Lab work is gonna be expensive, need control specimens.
Might have to call him "303MadScientistGuy".
OK I'll stop for a while.
Tin and antimony form a binary metalic compound.
This raises some questions for me i.e.:
1) do tin and copper form a similar compound?
2) does the formation of a binary compound change the miscability (sp?) fo its constituants in the solution( alloy)
3)What is the eutectic of copper in tin if it does not make a bianary compound?
I'm not sure where to go with all these questions or even if they matter to the pursuit of tough boolits. I'm just a curious sort (double meanings intended.)
Last edited by robroy; 07-25-2010 at 10:05 PM. Reason: edited because I can't spell
Hum, with a high Antimony alloy, you can heat treat plus water quench, to yield a hard shell and a softer core, which a Pb/Sn/Cu alloy could not replicate as far as I know.
Yes, CuSn.
Not exactly sure what you're asking. The formation of the binary compound is a result of the miscibility of it's constituents.2) does the formation of a bianary compound change the miscability (sp?) fo its constituants in the solution( alloy)
The Sn/Cu eutectic is Sn99.3/Cu0.7.3)What is the eutectic of copper in tin if it does not make a bianary compound?
First, someone needs to demonstrate unambiguously that copper 'toughens' lead bullet alloys. I have seen scant evidence of this. Copper hardens lead as a result of it's severely limited miscibility and the difference in atomic radius. Generally, the more miscible, and the more similar the atomic radius and electron configuration, the more an element toughens lead. To my knowledge, copper is not a leading contender.I'm not sure where to go with all these questions or even if they matter to the pursuit of tough boolits. I'm just a curious sort (double meanings intended.)
Curiosity is fully half the battle. Best of luck with your experiments.
I'd love to test this in a scientific way. Statics and strengths is a course from long ago and I'm working overtime till after Christmas (this jobless recovery is going to kill me). Having said that I have an Idea for a test rig, just not the time to build it and then drag out the old text books to refresh my memory.
Have, you seen evidence that other elements toughen lead ?
USMC 1980-1985
Generally, toughness is decreased as the solubility of the alloy component decreases. Tin will toughen lead, antimony generally will not. Short of a Charpy rig, this is why a clip-on ww will snap if bent, and the more Sb it contains, the sooner it will snap. A lead/tin alloy of the same dimensions will only bend, and not snap. As you know, the resistance to breakage under impact (or strain) is "toughness", as contrasted against "hardness".
Tin, bismuth, cadmium, and thallium are the best candidates for toughening, and zinc and copper lie on the other end of the scale. Very small additions of low-solubility metals may--however-- increase toughness. As always, theory guides, experiment decides, so I encourage folks to test their beliefs on this subject. Good luck.
High-fps camera footage of 20:1, 50/50, WW, heat treated high Sb, etc., and the first 3 with .6%Cu, hitting AR500 plate would be neat. Bonus points if all done a different velocities too. I imagine there are very few here equipped to do this though, much less with the time to do so. And not even sure if it's worth doing....
What's a good way to measure toughness? Maybe testing HPs in water would be the most convenient way as the petals would display brittleness?
Would shear strength coincide with toughness? Or would hardness interfere with a toughness measurement?
Should be simpler to construct (and interpret) a repeatable shear test than to film high-speed impacts.
Say, insert boolit into a hole through two offset plates, drop hammer from a measured height until control or test boolit is sheared.
Filmed impact tests would be more fun of course!
Yes, exactly-- greater shear strength under impact is a measure of greater toughness. Greater hardness usually does not increase toughness, but does not interfere with the measurement. They are two separate measurements.
It's always fun to watch bullets hitting a hard target! In this case, though, it may not offer much in the way of insightful testing, as there is simply too much energy involved-- more than enough energy to render any lead bullet into tiny fragments. It is somewhat like testing which bullet is tougher by using a stick of dynamite to blow them to bits.
There is some interesting reading on lead alloy toughness on-site in the Stickies & Classics forum. See http://castboolits.gunloads.com/showthread.php?t=40767. I might quibble slightly about the strict definition of 'toughness' and a few other terms/concepts in that well-constructed article, but the author does use an impact test, which is how one must test for toughness. One will immediately see that hardness and toughness are not tightly correlated, but the test was geared to measure both hardness and toughness, and locate the point where both were at a commmon maximum.
That combination of factors seems to be what most casters are looking for when looking for a "tough" bullet.
Sagacious, any plumbing copper you can buy will have a small percentage of phosphorous in it (this is added to all plumbing, hvac cu to allow high temperature brazing around 1200 deg F without the use of a flux). That being said a couple questions:
What effect if any would this have on the alloy made with the CU?
Second would the phosphorous allow the lead to alloy without being tinned?
Remember the average response time of a 911 call is over 4 minutes. The average response time of a .357 is around 1300 F.P.S.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |