High Copper Alloys- Lets discuss this further

[badgeredd]

Cderf

[Jim Flinchbaugh]

Jim - the data I have found indicates the Cu enriched will be 90% max hardness in 24 hrs.

This is what I'm seeing as well. Day after casting was hard, its been hanging in the same area since then.
To clear the muck again, we are not after "hard" with the Cu, we are after "tough & malleable"
You're post above could be construed as using Cu to harden the mix

[badgeredd]

Zxcvb

[kavemankel]

Cu alloying lead has been done for a long time but with modern testing techniques becoming cheaper we can send our own special blends in to have them tested so we may be able to tweak them ever more.
I Like reading this to see what other people are doing to make HC more viable for high speed rifle velocity

[303Guy]

I'm going to be dissolving the copper rather than the CS method. So, what alloy mix should I be looking for? What's the maximum tin I should be aiming for? wheel weights don't just lie around in tyre shops in my parts - those all end up as sinkers. I have plenty of tin at the moment so I don't mind using a bit of tin to get the end effect. I do know high copper alloy 'hardens' quite quickly and that in itself is a good reason to use it. I do believe antimony is an additional requirement but how little do I need? And how will negate the malleability thing we are after? Does arsenic make any difference? Is it beneficial? I'm kinda thinking a whole bunch of grain refiners together might make a good alloy for us with each being in moderate amounts, like at the solubility limits of each?

[303Guy]

Thanks popper. It's the antimony I'm short of.

Any suggestions on how to 'measure' alloy performance? One test I've thought of but never a round to to the dual impact test, that being comparing the impact of a fast but light object and a slow but heavy object. The idea being that the impact force should be the same. A third one would be a static load with the same force. That would be with a steel ball of the same diameter in the nose of the impactor. Another test would be a heavy flat object dropped from a standard hight i.e. a hammer test. Field tests are going to be tricky but that'll be the most critical.

[badgeredd]

fghjk

[45 2.1]

There are some things I would like to know........ from the folks who started this current copper addition to an alloy.

1. What you think is the best ideal alloy percentages for all known items in the alloy.
2. Casting parameters... WD or AC, casting temps, etc. for uniform results
3. Time vs hardness parameters
4. Time vs diameter growth parameters
5. Time to alloy stability
6. Finally, just what do you gain (or loose) by a balanced alloy.... cause and effect in specifics with examples.

Granted, by what i've seen in the past and with the two alloy mixes Edd gave me, this could be useful for several common problems casters have, but it also interjects some problems for other use parameters also. What is very useful is military duplication loads, high velocity loadings as well as putting sub diameter casting molds back in use.

Soo, how about informing everyone just what to expect?

[badgeredd]

yhnbg

[badgeredd]

Uhbvg

[357maximum]

Popper/303Guy/Edd

Is there a way to use/incorporate "spine testers" that are used to test what weight bow wooden arrows will shoot. Just trying to spark a thought.

[45 2.1]

6. Finally, just what do you gain (or loose) by a balanced alloy.... cause and effect in specifics with examples.
Again as I have said in the past, it is my opinion that a balanced alloy will give the greatest benefits.

... it also interjects some problems for other use parameters also. Exactly what problems are you asking about?

One thing we have noticed is one "needs" to cast at a higher temperature. I am assuming this is due to the copper content.

I have changed my idea on what might constitute a balanced alloy. Therefore I am experimenting with an mix addressing the idea of balance from 2 different directions. We are experimenting and learning from the results. The more people that get on board with the idea, the faster "rules" can be arrived at, IMO.

As for what to expect, I suggest that one try it to help us learn "what to expect."

Edd

OK Edd...... the above questions are in relation to some things I have read recently and some old material I learned in the TAM lab at school. A poster on this site related an alloy (basically 1.5% of each in one and 2% of each in another...IIRC) that had equal proportions of tin and antimony (basically what you have said is a balanced alloy, but not quite actually) being a stable alloy (due to the tin binding the antimony so no hardness growth occurs or diameter change for that matter) after a couple of days. I've heard Bruce say the copper alloy stopped growing in hardness after a couple of days and Mike and you say it grows and hardens to about 6 months. Others folks report diameter changes by measurement. Quite a difference in results. The alloy mixes you gave me don't grow or harden after a few days as I have some about 7 months old. What I see is a great difference in results with no consensus as to what is it and whats it do. Got some answers there?

[badgeredd]

Rfvbg

[btroj]

As for testing I would think 2 tests are in order. First, to test for toughness as opposed to brittleness a large weight dropped from a known height would work. Compare to other known alloys. I would be happy with something that doesn't fracture when hit hard wins big hammer. I know that monotype breaks into shrapnel and disappears if hit like that.
The second test is accuracy at higher velocity with the same alloy.

If it shoots well at 2400 fps or better and isn't so brittle that it fractures when hit with a hammer I ask this- what more do we need? Higher velocities generally mean hard alloys, those tend to be brittle.

This is a very subjective test but I don't care if it can be quantified. Results are what I want to see. Good accuracy, higher velocities, and good terminal ballistics- no fragmenting bullets.

[357maximum]

Bob

It grows, Bruce was mistaken or you heard him wrong while you were waiting your turn to talk....pure and simple it grows. It is a special use alloy that You yourself have said is not worth much. I would not be upset if you were trying to learn something, but...well I will keep that door shut, that closet is a mess.


Why the change of heart, thought you did not care and that you had already been there done that did not want it????????? Please and I am publicly begging of you ....STOP trolling and let those who want to learn and SHARE their findings do so in peace. I am trying to ask nicely, the next time I ask, one of the mods will likely have to give me a time out and you ain't worth the hassle. Those of us that KNOW you KNOW what you are up to, so please just stop. PLEASE

Copper alloys have been around a long time.... and have been written about that long also. The problem before was replacing what worked after it ran out with the same thing. Now that is not so much of a problem....... BUT, what do you actually have with that copper alloy? I suspect it will be hard besides being tough..... and you should be able to shoot it at basically full velocity. If you use a boolit design with a big flat meplat, all is well a good until it decelerates to a certain velocity. Conventional designs with a small meplat will get you a FMJ and the performance associated with it. Having seen 357 Maximum recovered boolit pictures it looks like its a solid FMJ performance type that barely looses weight. I don't think it will expand and his pictures show that........... Basically its a special use alloy. I've shot enough varmints with solids, both with small and large meplats to know whats gonna happen...... myself I'll choose an expanding boolit.... just like what the jacketed bullet industry does for conventional usage.

[badgeredd]

Uhbyg

[btroj]

I am thinking about what can be done with a proper fitting bullet in my 375 H&H.
A 270 gr cast bullet at 2600 or so would be awesome.

[357maximum]

I am thinking about what can be done with a proper fitting bullet in my 375 H&H.
A 270 gr cast bullet at 2600 or so would be awesome.

You must have missed the memo..."ALL THE MASTADON ARE DEAD" Going by what my whelen will do your awesome goal is very do-able. A 270 grainer @ 2600...what more do we need?.... indeed.

[btroj]

Well, in Nebraska we do feed our deer corn........

[45 2.1]

Since you said you had messed with babbit in the 80s, I thought you may have some input, ergo the reason I gave you some of my babbit to work with.
Edd

I did...... the problem was one of finding the same thing again (that didn't happen though).... each lot was a little different. That was fine for general shooting, but not very good for experimenting. That is why I dropped it and not knowing just what it was or what it had in it.