Lead and Zinc? - The Firearms Forum

steve4102 · 10-13-2012, 10:20 PM

As you guys know I am new to bullet casting. I just purchased a bunch of WW ingots on-line for a pretty good price. They look good to me, but as I said I'm new so what do I know.

When I melt these down to make bullets what should I look for as far as Zinc or other unwanteds?

Thanks

aa1911 · 10-13-2012, 11:52 PM

Zinc has a higher melting point (but not too much higher) so when you've got a good base of melted lead, anything that doesn't melt pretty quick, remove immediately. It tends to float as do the clips so it's not too difficult but if you let it sit, it will melt in your alloy.

http://castboolits.gunloads.com/showthread.php?t=66241

WA state outlawed WW lead, pretty bummed... they're all zinc now...l

howlnmad · 10-14-2012, 07:37 AM

The only thing is that these are already ingots so it will depend on the original owner if he had zinc mixed in and ran a hot enough temp to melt it. You pretty much won't know until you pour some boolits. I think, I've never had a zinc problem before.

aa1911 · 10-14-2012, 11:48 AM

ah, thought you meant original WW's, they are already melted into ingots?

doubtful you're gonna separate those without losing the antimony also.

myfriendis410 · 10-14-2012, 01:07 PM

You could remelt and flux the top with a lot of sawdust which will remove a lot of the impurities. Molten zinc is apparently highly toxic when heated to it's vapor point and is quite a bit higher than the ww melt temp. However; fluxing with sawdust will remove other impurities that can affect the overall quality of the finished cast bullet.

gun-nut · 10-14-2012, 02:10 PM

If there,s zinc in the mix it will have a dull and wrinkled look to it as it will have a blue and purple color to it on top of the lead pot. I found that out one time myself. Thought i had lead but did not. I was able to blend new lead in and it did break up the PPM of the zinc. It will take a crap load of lead to do it. You can also break the zinc ingot and if it has a grain structure to it its zinc, lead has no grain structure to it. I will see if i can find it and post a pick of it.

JLA · 10-14-2012, 05:12 PM

yep. and once alloyed it is incredibly difficult to separate it.

Keep your pot temp at around 660 degrees and no hotter. Pure lead melts at that temp and all the good metals that make a good lead alloy melt at a lower temp. all the stuff that ruins your mix melts at more than 700 degrees.

So maintain a 650-660 degree pot and flux often. Keep the floaties skimmed off.

I made my own flux when i casted. Home made bullet lube and sawdust, mixed into an even slurry and let set to harden in a pan. Then cut into cubes about 1/2"X1/2"

soundguy · 10-15-2012, 07:28 AM

interesting thread. I do lots of electronics and plumbing and repair work on old tracotrs and large equipment.. I do soldering daily... i find this thread interesting as I work around different solder alloys alot.

zinc will wet / stick to aluminum.. but lead won't. not sure if that helps anyone..

gun-nut · 10-15-2012, 04:10 PM

Its not the best pick but you can see that zinc has a grain structer to it.

JLA · 10-16-2012, 08:11 PM

That aluminum trick is how i used to get the zinc outta my mix back when i first started casting.

Aluminum melts at a much higher temp than any lead compatible alloy but zinc will stick to it and lead wont. so it makes a good catch for unwanted zinc.

howlnmad · 10-16-2012, 08:26 PM

Quote:

Originally Posted by JLA

That aluminum trick is how i used to get the zinc outta my mix back when i first started casting.

Aluminum melts at a much higher temp than any lead compatible alloy but zinc will stick to it and lead wont. so it makes a good catch for unwanted zinc.

That I did not know. Good info to have.

aa1911 · 10-16-2012, 11:20 PM

I guess if you ran the pot in between lead and zinc temps, you could just scrape off the dross that forms (the oatmeal), and add antimony afterwards if desired? the antimony has a 1100' or so melting temp correct? Better to have softer lead than hard lead with zinc contaminating it.

steve4102 · 10-16-2012, 11:31 PM

Update:

I cast about 200 10MM bullets last night and everything went great. Clean, full mold, no sags, nothing that would indicate Zinc in the mix.

I ordered more.

Thanks for all your help.

howlnmad · 10-17-2012, 01:18 AM

Quote:

Originally Posted by steve4102

Update:

I cast about 200 10MM bullets last night and everything went great. Clean, full mold, no sags, nothing that would indicate Zinc in the mix.

I ordered more.

Thanks for all your help.

Ummmmmm.... Where are the pics?

10-13-2012, 10:20 PM	#1
steve4102 Former Guest Join Date: Jan 2006 Location: Minnesota Contributor Posts: 2,760	Lead and Zinc? As you guys know I am new to bullet casting. I just purchased a bunch of WW ingots on-line for a pretty good price. They look good to me, but as I said I'm new so what do I know. When I melt these down to make bullets what should I look for as far as Zinc or other unwanteds? Thanks -->

10-13-2012, 11:52 PM	#2
aa1911 Advanced Senior Member Join Date: Dec 2010 Location: Pacific Northwest Posts: 3,110	Re: Lead and Zinc? Zinc has a higher melting point (but not too much higher) so when you've got a good base of melted lead, anything that doesn't melt pretty quick, remove immediately. It tends to float as do the clips so it's not too difficult but if you let it sit, it will melt in your alloy. http://castboolits.gunloads.com/showthread.php?t=66241 WA state outlawed WW lead, pretty bummed... they're all zinc now...l __________________ "Loud noises don't end gunfights.... well placed shots do."

10-14-2012, 07:37 AM	#3
howlnmad Advanced Senior Member Join Date: Nov 2008 Location: Harriman, Tn Contributor Posts: 2,565	Re: Lead and Zinc? The only thing is that these are already ingots so it will depend on the original owner if he had zinc mixed in and ran a hot enough temp to melt it. You pretty much won't know until you pour some boolits. I think, I've never had a zinc problem before. __________________

10-14-2012, 11:48 AM	#4
aa1911 Advanced Senior Member Join Date: Dec 2010 Location: Pacific Northwest Posts: 3,110	Re: Lead and Zinc? ah, thought you meant original WW's, they are already melted into ingots? doubtful you're gonna separate those without losing the antimony also. __________________ "Loud noises don't end gunfights.... well placed shots do."

10-14-2012, 01:07 PM	#5
myfriendis410 Senior Member Join Date: Mar 2011 Location: Lompoc California Posts: 542	Re: Lead and Zinc? You could remelt and flux the top with a lot of sawdust which will remove a lot of the impurities. Molten zinc is apparently highly toxic when heated to it's vapor point and is quite a bit higher than the ww melt temp. However; fluxing with sawdust will remove other impurities that can affect the overall quality of the finished cast bullet. __________________ Life's too short to shoot an ugly gun.....

10-14-2012, 02:10 PM	#6
gun-nut Senior Member Join Date: Jan 2011 Location: ohio Contributor Posts: 931	Re: Lead and Zinc? If there,s zinc in the mix it will have a dull and wrinkled look to it as it will have a blue and purple color to it on top of the lead pot. I found that out one time myself. Thought i had lead but did not. I was able to blend new lead in and it did break up the PPM of the zinc. It will take a crap load of lead to do it. You can also break the zinc ingot and if it has a grain structure to it its zinc, lead has no grain structure to it. I will see if i can find it and post a pick of it. __________________ Don't retreat just reload.

10-14-2012, 05:12 PM	#7
JLA TFF Moderator/Host Join Date: Feb 2007 Location: Heart Of Texas Contributor Posts: 17,305	Re: Lead and Zinc? yep. and once alloyed it is incredibly difficult to separate it. Keep your pot temp at around 660 degrees and no hotter. Pure lead melts at that temp and all the good metals that make a good lead alloy melt at a lower temp. all the stuff that ruins your mix melts at more than 700 degrees. So maintain a 650-660 degree pot and flux often. Keep the floaties skimmed off. I made my own flux when i casted. Home made bullet lube and sawdust, mixed into an even slurry and let set to harden in a pan. Then cut into cubes about 1/2"X1/2" __________________ It takes 43 muscles to frown, 17 to smile, and 3 for proper trigger squeeze. The latest caliber or gear is no substitute for experience and skill. Rifles and cartridges don't make hits -- shooters do. Fact of life: After Monday and Tuesday, even the calendar says WTF! Last edited by JLA; 10-14-2012 at 05:14 PM..

10-15-2012, 07:28 AM	#8
soundguy Advanced Senior Member Join Date: May 2012 Location: florida Contributor Posts: 4,406	Re: Lead and Zinc? interesting thread. I do lots of electronics and plumbing and repair work on old tracotrs and large equipment.. I do soldering daily... i find this thread interesting as I work around different solder alloys alot. zinc will wet / stick to aluminum.. but lead won't. not sure if that helps anyone..

10-15-2012, 04:10 PM	#9
gun-nut Senior Member Join Date: Jan 2011 Location: ohio Contributor Posts: 931	Re: Lead and Zinc? Its not the best pick but you can see that zinc has a grain structer to it. Attached Images __________________ Don't retreat just reload.

10-16-2012, 08:11 PM	#10
JLA TFF Moderator/Host Join Date: Feb 2007 Location: Heart Of Texas Contributor Posts: 17,305	Re: Lead and Zinc? That aluminum trick is how i used to get the zinc outta my mix back when i first started casting. Aluminum melts at a much higher temp than any lead compatible alloy but zinc will stick to it and lead wont. so it makes a good catch for unwanted zinc. __________________ It takes 43 muscles to frown, 17 to smile, and 3 for proper trigger squeeze. The latest caliber or gear is no substitute for experience and skill. Rifles and cartridges don't make hits -- shooters do. Fact of life: After Monday and Tuesday, even the calendar says WTF!

10-16-2012, 11:20 PM	#12
aa1911 Advanced Senior Member Join Date: Dec 2010 Location: Pacific Northwest Posts: 3,110	Re: Lead and Zinc? I guess if you ran the pot in between lead and zinc temps, you could just scrape off the dross that forms (the oatmeal), and add antimony afterwards if desired? the antimony has a 1100' or so melting temp correct? Better to have softer lead than hard lead with zinc contaminating it. __________________ "Loud noises don't end gunfights.... well placed shots do."

10-16-2012, 11:31 PM	#13
steve4102 Former Guest Join Date: Jan 2006 Location: Minnesota Contributor Posts: 2,760	Re: Lead and Zinc? Update: I cast about 200 10MM bullets last night and everything went great. Clean, full mold, no sags, nothing that would indicate Zinc in the mix. I ordered more. Thanks for all your help.