My first range lead and I got zinc'd!!!

[Yodogsandman]

I smelted just two pot fulls of range lead to try it out. I filled the pot and went in the house for a half hour, then went out and removed the debris. I fluxed with oak sawdust and paraffin. It looked a little funny but, what did I know about range lead? I poured off the ingots and let cool. I filled my bottom pour Lee pot and added a little tin and two ingots of pure lead. This melted and I used paraffin again to get the tin mixed in. It didn't mix in, I thought my pot wasn't coming up to temperature, it's 25 years old. I skimmed off the top and then skimmed off the top. I then skimmed off the top and parrafin'd again. Still some sludge on top. I tried to cast some boolits and had a hard time with the mold filling out, tried another mold, same thing. So, I've come to the conclusion that I got zinc'd!!! What would be in range lead that would cause this? Did my temperature, while smelting, get high enough to separate the zinc and copper from the bronze? Off to find some sulfur to try that fix-it trick!

BTW, I emptied my bottom pour, cleaned it a bit and re-filled with COWW and a little tin. No problems! It's got to be zinc!

Moderator, Please re-post this in the "lead and lead alloys", my bad.

[xacex]

I would add copper to replace the zinc. Copper has been getting added to all of my alloy now, and zinc works as a better replacement than tin.

[tomme boy]

Your pot is not up to temp. Try melting that stuff you scooped off and I bet it will melt back in. First get it up to temp.

[Yodogsandman]

Your pot is not up to temp. Try melting that stuff you scooped off and I bet it will melt back in. First get it up to temp.

I tried that a few times, added parrafin, stirred it in real good. I've got about a pound of grey/silver sludge that floats to the top. I skimmed most of it off into the ingot mold. More keeps coming back. The boolits come out very shiny and mirror-like. I had to run about 200 casts to get 20 boolits and it did'nt seem to matter too much how hot I got the mold or alloy. I couldn't even get my boolits to frost, which is were I back off and slow down a bit.

I have some powdered sulfur now to try but, I don't know how that's going to work. New territory for me, just like the range lead!

[runfiverun]

frosting is caused by antimony.
you need to double check your pot temp....seriously.
if you have zinc it comes up as an oatmeal looking gunk under the surface and it goes to the center of the pot when you stir it.

adding tin actually allows the alloy to accept a bit more zinc, it doesn't make it separate.
zinc and tin are best buddies.
if you have suspect tin I'd look at that.
many metals [or minerals carried in the alloy, calcite/kirksite] appear to be tin [white metal] but are not compatible with lead alloys and will cause casting issues too.

[Yodogsandman]

I guess you could say this sludge looks grainy like metal oatmeal.

The tin I added was in the form of commercial 50/50 bar solder.

The molds I used were both new, never used and may have needed to be "cycled" a few times. One Lee and one Lyman.

What could be in the range scrap that would cause it? Non-lead bullets? Steel core? Or as mentioned, bronze being leached?

Everything returned to normal after I switched back to COWW. I don't suspect the pot anymore.

[fred2892]

Zinc leaching from bronze? Reading your original post I don't see what you used that was bronze.

[Vinne]

That's one thing I always worry about. I bring the pot up slowly in an effort to avoid any zinc I may have missed during my hand sort. As far as range lead, I don't know of anything that would act that way. Jackets and trash should float to the top during fluxing. Years ago I got 300 lbs of indoor range lead and the main waste was sand with some jackets but no problem with any of the melts. Try a lower temp. Hope you can recover from this!!

[tazman]

That's one thing I always worry about. I bring the pot up slowly in an effort to avoid any zinc I may have missed during my hand sort. As far as range lead, I don't know of anything that would act that way. Jackets and trash should float to the top during fluxing. Years ago I got 300 lbs of indoor range lead and the main waste was sand with some jackets but no problem with any of the melts. Try a lower temp. Hope you can recover from this!!

I recently got hold of approximately 400lb of indoor range lead. My smelting results were identical to yours.
I ended up with 300lb of good lead ingots. It works really well in my pistols.

[leeggen]

Before you panic test the sludge to see if it is infact zinc. Muratic acid dripped on the metal will bubble and fizz if zinc.
CD

[Yodogsandman]

With COWW I end up with 20 ingots and the clips, with the range lead, I got 8 ingots and some were thin. The rest in the pot was garbage! Sand, little rocks, jackets, etc. I had to dig to find any lead at the bottom! But, I did end up with 8 ingots that just took time and a little effort to get. Until I realized I got zinc'd!

[Magana559]

I don't see how you would have zinc in range lead. Maybe if someone shot a ton of zinc bullets.

[runfiverun]

it could also be a high copper or nickel content they will both make an alloy not behave properly.
it could of course just be zinc, it's not unheard of to cast and shoot zinc boolits.

[guncheese]

im betting its just the dead soft lead from the bullet cores
it melts at a lot hotter temp then what your used to casting with
and straight lead makes a very shiney ingot/bullet
bring up the temp, what has your thermometer said?

[guncheese]

it's not unheard of to cast and shoot zinc boolits.

ive run across a few in my berm mining expeditions they float nice in the smelt

[Yodogsandman]

I've never felt the need for a thermometer, till now!

Wonder if it was tracer rounds? I don't know what's in them. I saw a new sign crop up about a year ago saying not to use them. I guess some manufacturer could use zinc to increase velocity in their bullets.

With the amount of debris in the pot, nothing could float. I had to dig to find the molten lead.

My little 10# Lee bottom pour is 25+ years old, I run it on the highest setting and use the sprue puddles to cool it when I need to.

[Defcon-One]

Honestly, it could be anything! Maybe even something like Bismuth, but most likely it is either very soft lead as stated above (so temp up) or high Antimony lead (so temp up).

An acid test of the skimmed metal will confirm Zinc fairly easily. Barring a positive result there, then it could be anyones guess.

This is one reason why I avoid range lead, it is ALWAYS pot luck!

[gpidaho]

Yodog: ITS ALWAYS SOMETHING AYE! Some bargains just aren't as good as they seem to be. Don't know if your range has shotgun use or not, Ive had some casting fill out problems when scrap included high antimony shot, Range scrap just isn't worth the trouble to me. GP

[Yodogsandman]

Any chemists out there? I found some 10% solution of hydrachloric acid, put it on the ingot that I had skimmed off of suspect zinc material. I got very little reaction, it turned that spot a dark color. No fizzing or anything. I did get fizzing when I diluted it with sodium bicarb solution. Now what do I do? Was the solution strong enough for the test?

[plmitch]

Another reason range waste in not worth the time when clean lead is easily available.