Got a new alloy!

Spindrift

Well-Known Member
So far, I’ve been casting with nuclear medicine lead, since I have a good source for it at my local hospital (where I work). It is around BHN 15, a very versatile alloy. But for some reason, my alloy will only fill out well at ridicilously high temps.

Anyway, I made an arrangement with a local indoor range, where they shoot .22 subsonics, and a little airgun pellets. Actually, they shoot almost exclusively RWS .22lr (contents of bullet traps should be very consistent). I can come there, and retrieve lead from the bullet traps. This club is a non-profit club that teach kids rifle shooting, so I gladly pay them a little for the lead.

Smelted a bunch of these .22 bullets , mixed with 2% pewter and cast a few bullets. Now, this was something else! Very good fill-out, at normal casting temperatures. Tried some «difficult» moulds, and got almost no culls.

I tested BHN on fresh bullets. Air cooled and water quenced actually read the same, BHN 8. Then I tested the same bullets today, after about 10 days; BHN 12. A bit harder than I had expected, actually. Should be an excellent allround alloy. And castability is so much better than what I have been using so far. I think my general bullet quality should increase with this alloy.

Will shoot some tomorrow :)
 

Spindrift

Well-Known Member
That sounds like a good idea. The hardness of the two alloys seem to be pretty similar. I had expected the range scrap to be softer.
 

Ian

Notorious member
The range scrap probably has 2-3% antimony in it which doesn't make it all that tough...until you add tin.
 

DHD

Active Member
That sounds like a good idea. The hardness of the two alloys seem to be pretty similar. I had expected the range scrap to be softer.
I would have expected both of your alloys to be softer than they turned out. I try to stay around 10-12 bhn myself. Not an alloy expert even though I've cast for 20 years. For about 12 of those 20 years was strictly casting 20/1 for BPCR's.

I also have some Isotope lead, but I added tin when I melted the Isotope containers. It filled out in my MP Molds just fine. I had read it was more or less equivalent to COWW. I wonder now yet it casts fine bullets that weigh to +/- .5 grain of my other alloy (2/3 COWW 1/3 pure lead). FWIW, I cast at 750°.

Maybe so much of what I know just isn't so...
 
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Spindrift

Well-Known Member
Cast some bullets with a relatively new MP311-410, 2cav HP- mould. For some reason, getting good fill-out with my old alloy has been difficult with this mould. With my new alloy, it was a breeze!
I realize this is not exactly breaking news, or of general interest; «Spindrift finds a completely normal alloy!». But it just makes me so happy, I had to tell someone :)
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