casting with zinc alloy
- Thread starter jbunny
- Start date
Do you mean casting bullets?
Tried casting bullets from a zinc alloy and found cutting the sprue very difficult because the zinc alloy is very hard. The bullets weigh about 2/3 what lead does. IIRC the alloy i used was called Kirksite.
This was tried by hanloaders in WWII when jacketed bullets were unavailable. Heard there were high pressures reported because the bullets were hard all the way through and engraved hard.
Tried casting bullets from a zinc alloy and found cutting the sprue very difficult because the zinc alloy is very hard. The bullets weigh about 2/3 what lead does. IIRC the alloy i used was called Kirksite.
This was tried by hanloaders in WWII when jacketed bullets were unavailable. Heard there were high pressures reported because the bullets were hard all the way through and engraved hard.
Green; i a'm glad u replyed. i know now that i'm not the only crazy on
this list. LOL. i have been experimenting the last 2 days with lead
zinc alloy. wheelweight lead and zinc makes a puty. pure lead and
zinc mix 50-50 make a eutectic alloy. i cast a bunch today and my 44 cal
240 gr swc normaly weigh 250gr with #2 alloy. with this zinc alloy
there around 136 gr. i will try shooting some tomorrow. i plan on shooting
them dry, no lube. they are as hard as copper. here is a few pics on my
make shift viberator for casting. works like a hot dam. a old sears hair
clipper that u could not hang on to. i removed the 2 screws that held the cutter head on an bolted it on the the bottom of the c frame. the other
pic is of the bullets and my princess auto hardness tester. u can see the
bullet on the left with the lube is a lead bullet with the hardness punch on top. the zinc bullets have a very shallow punch mark. more later
Ken; i wear a painting resperator when casting and the doors are open.
i got to try these out today. YAAAAAAAHHHHOOOOOOOO.
loaded with 14 gr of unique, 2000 fps, 3 in groups at 100 yds.
the bullet on the left is lead bullet water quench. notice the wide
deep crater from the hardness tester. the middle one is zinc and
the one on the right is a barnes solid copper. notice the copper and zinc
craters are the same size, same hardness.
in this pic is 2 recovered zinc bullets from a dry pine block,
7 in penetration, the barrels are mirror clean. these were loaded
dry, no lube. they were sized with a lee sized with no drag and less
effort that alox lube lead bullets.jb
There is thread on Cast Boolits about using sulphur to separate zinc from molten lead.
http://castboolits.gunloads.com/showthread.php?p=679073#post679073
There are no toxic lead fumes emitted in the casting process - the temperature is far too low for that to occur. Neither is any measurable amount of lead absorbed through the skin by handling lead bullets, but it can be ingested. The same can be said for zinc.
Funny that this thread would pop up the day after I smelted some zinc wheelweights into ingots. I only see about 1% zinc and 3% steel in what I have picked up over the years, and it was only in the past year that I've saved the zinc.
I would think that zinc would make a crappy bullet - very light for its size, and hard (and brittle). Given that and its cost, a lead alloy or pure copper makes a much better bullet, but I appreciate someone experimenting.
How soft is that alloy? Did you try to improve it with more zinc?
Did you mean 50% weight pure lead and 50% weight zinc? Just 136 gr? If I have it right 50/50 alloy should be about 83% of pure lead. Since those 250 gr bullets from No. 2 alloy are usually heavier when cast from wheelweight, I would expect that bullet from noted alloy should be about 210-215 gr.
BTW, those bullets are just beautiful. Let us know what accuracy is.
Regards, Onty.
they are way more accurate in my rifles than wheelweight lead.
so far with 1 range session 3 in groups at 100yd. with win bulk
240 gr bullets the same rifles(1 have 3 44 mags) shoot 1 big ragged hole
at 100 yds with the bullets touching the rifleing. i loaded these zinc
bullets a little shorter for the first time. i was playing it safe.
they shot good enough to make me order a 4 lb keg of unique today.
as for bullet weight, the only formula i use is the SWAG formula.
my next step is to modify the mould. i'm gona remove the sprue cutter.
i'm gona try casting with the big lee electric melter as the temp seems
to be more criticle.
jb
http://www.muggyweld.com/melting.html
this is the melting temp of metals. pure lead and zinc
make a eutectic alloy that melts around 670 deg far.
http://www.tedpella.com/company_html/hardness.htm
this is the material hardness tables. zinc and copper are about equal.
my hardness tester more or less confirmed that.
the coefecion of friction of zinc is way better than copper or lead and when
i sized these dry , and i could tell that there was way less drag
than lead bullets. this is turning out to be a worth while project fo me
anyway.
I think this info would cause a fair bit of interest on the Castboolits site.
Lots of guys over there that are processing wheel weight over a turky fryer burner, and getting the zinc into their alloy.
Anyway, keep on posting this stuff! ood info to know.
Makes me wonder how fast a really light 225107 would be able to go.
Cheers
Trev
Lots of guys over there that are processing wheel weight over a turky fryer burner, and getting the zinc into their alloy.
Anyway, keep on posting this stuff! ood info to know.
Makes me wonder how fast a really light 225107 would be able to go.
Cheers
Trev
Hello all,
First, allow me to introduce myself. I’m a 50-year-old+ shooter, hunter, reloader, caster, collector from the US of A. I’ve spent my whole life around guns and shooting; my grandfather was a gun dealer and sold guns in the back of his general store. The store was in a tiny river town with a one-sided main street, I was shooting as soon as I could walk and hold a gun at the same time.
Also, I’m an import (of sorts) from the castboolits site, one of our members over there posted a link to this thread. This is quite interesting and I’ve a couple questions...
jbunny,
When say your alloy is a 1:1 lead/zinc, is that by weight or by volume? What I mean is, did you weight out say, 10-pounds lead and 10-pounds zinc, or did you use say, 5 ingots of lead and 5 ingots of zinc (volume)? It would make a big difference given the difference in mass of the two metals.
The other question is about the ‘pure lead’. What is the source of your ‘pure lead’, is it certified or is it some sort of scrap metal? I’m not questioning your word, I’m just trying to determine what elements present in wheel weights cause the casting problems when alloyed with zinc.
Thanks a bunch...
WS
First, allow me to introduce myself. I’m a 50-year-old+ shooter, hunter, reloader, caster, collector from the US of A. I’ve spent my whole life around guns and shooting; my grandfather was a gun dealer and sold guns in the back of his general store. The store was in a tiny river town with a one-sided main street, I was shooting as soon as I could walk and hold a gun at the same time.
Also, I’m an import (of sorts) from the castboolits site, one of our members over there posted a link to this thread. This is quite interesting and I’ve a couple questions...
jbunny,
When say your alloy is a 1:1 lead/zinc, is that by weight or by volume? What I mean is, did you weight out say, 10-pounds lead and 10-pounds zinc, or did you use say, 5 ingots of lead and 5 ingots of zinc (volume)? It would make a big difference given the difference in mass of the two metals.
The other question is about the ‘pure lead’. What is the source of your ‘pure lead’, is it certified or is it some sort of scrap metal? I’m not questioning your word, I’m just trying to determine what elements present in wheel weights cause the casting problems when alloyed with zinc.
Thanks a bunch...
WS
Barrel erosion?
Have you noticed any throat erosion in your barrel? I was talking to an old-timer about casting bullets not to long ago and he was telling me that he had a big stash of a lead/zinc alloy that he used to use for casting bullets for his 30-30. After about 200 or so rounds (from new) he said the barrel was almost completely shot out.
He figured the zinc was the culprit, and I might be inclined to agree with him. IIRC there used to be a line of bullets that were sold as cleaning bullets for handguns that had a zinc band at the back and they were used to clean heavy leading from barrels. They had a warning on them, to avoid excessive shooting using those bullets.
I think that Zinc (although just as hard as copper) lacks the self lubricating qualities of copper.
Any signs of excessive wear? You said the barrels were mirror bright after shooting.
Have you noticed any throat erosion in your barrel? I was talking to an old-timer about casting bullets not to long ago and he was telling me that he had a big stash of a lead/zinc alloy that he used to use for casting bullets for his 30-30. After about 200 or so rounds (from new) he said the barrel was almost completely shot out.
He figured the zinc was the culprit, and I might be inclined to agree with him. IIRC there used to be a line of bullets that were sold as cleaning bullets for handguns that had a zinc band at the back and they were used to clean heavy leading from barrels. They had a warning on them, to avoid excessive shooting using those bullets.
I think that Zinc (although just as hard as copper) lacks the self lubricating qualities of copper.
Any signs of excessive wear? You said the barrels were mirror bright after shooting.
I don't cast my own bullets but I shoot cast. This is an interesting thread but I have a question. If you eventually end up with some zinc fouling in a barrel, what would you clean it with? Will standard solvents work on zinc? Might be something to look into before you get to that stage.
mr WS; did u just come from a cast bullet list where the list owners
name is "chas"????
update on todays findings. lead and zinc is suposed to form a eutectic
alloy as i was told by a metalergist on an other list. well my pure lead
(scrap but soft by the fingernail test) zinc alloy did not mix. that why my bullets weigh 136 gr. pure zink. when i dipped from the bottom the bullets were soft and weighed almost 250 gr. i will be talking to alloy specialist
on monday. maybee i shouldof used borax for fluxing instead of parafin wax.
i will know more on monday. i have the hard sprue cutting problem licked.
the vibrator is working great and the bullets are looking great. i have a range date on tuesday. more later jb
update; i whent shooting yesterday to test some more. 15 gr of unique
gave 2160 fps average while 16 grs gave 2280 fps. accuracy was the
####s. 8 in group. barrel looked fouled up. it cleaned up good with a few
strokes with a bronze brush. that was a releif. now for some good news
bad news. i just got of the phone to purity casting alloys in surry, bc.
http://www.purityalloys.com/index.html
i told him what i was doing and he quoted me a price of $7.50 a lb
in 25 lb lot delivered to Quesnel. that would be about 15 cents a
bullet. for gravity casting he recomended za-12 alloy. i just checked
there
chart and za-3 is 82 brinell and the za12 is 105 brinell. i asked about
alloy with something to make it fill in easier and i told him i used a vibrator
and he said the that was a good idea. thats when he recomended the za-12
alloy. he did'nt think the electric melting pot would be hot enough.
i should not be useing iron or steel melting pot or ladle. it don't take
very long for the zinc to pick up iron from the pot and it makes it harder
ans harder to cast, which is whats happening to me.. use only graphite
crucibles and graphite or ceramic ladles. here i thought when i had the sprue
cutting difficulty solved , i had it licked. i will give it one more crack
tomorrow. jb
gave 2160 fps average while 16 grs gave 2280 fps. accuracy was the
####s. 8 in group. barrel looked fouled up. it cleaned up good with a few
strokes with a bronze brush. that was a releif. now for some good news
bad news. i just got of the phone to purity casting alloys in surry, bc.
http://www.purityalloys.com/index.html
i told him what i was doing and he quoted me a price of $7.50 a lb
in 25 lb lot delivered to Quesnel. that would be about 15 cents a
bullet. for gravity casting he recomended za-12 alloy. i just checked
there
chart and za-3 is 82 brinell and the za12 is 105 brinell. i asked about
alloy with something to make it fill in easier and i told him i used a vibrator
and he said the that was a good idea. thats when he recomended the za-12
alloy. he did'nt think the electric melting pot would be hot enough.
i should not be useing iron or steel melting pot or ladle. it don't take
very long for the zinc to pick up iron from the pot and it makes it harder
ans harder to cast, which is whats happening to me.. use only graphite
crucibles and graphite or ceramic ladles. here i thought when i had the sprue
cutting difficulty solved , i had it licked. i will give it one more crack
tomorrow. jb
another update; there is ceramic coatings for steel crucuble pots and
ladels. that is good news. i had misrable range time this mornibg
with horizontal rain ect. this first pic is my bullet mould with the modified
sprue cutter with the rotary incline plane. i know u will say 10,000 comedians
out of work and u trying to crack jokes. no effert to cut all 4 zinc sprues
and quite fast too. i welded the rod of center to the bolt so the vibrator
would not screw the bold out while pouring.
this pic is self explanatory. i'm haveing trouble getting the bullet base
to completly fill and is worst now. i suspect iron contamination from
the pot and ladel. i loaded 5 bullets with the best bases with 14 gr
of unique with 2160 fps av, left target. in the right target same except
i machined the bases flat and true. quite a differance. so if u want to
cast with zinc coat your metal with a ceramic coating and AFAIC
u need a nose pour mould. the bullets look good except the base and a
nose pour would be just the ticket. OBTW i'm in the market for a
44 cal and 357 cal nose pour moulds. pm me please if u have one to sell.
ladels. that is good news. i had misrable range time this mornibg
with horizontal rain ect. this first pic is my bullet mould with the modified
sprue cutter with the rotary incline plane. i know u will say 10,000 comedians
out of work and u trying to crack jokes. no effert to cut all 4 zinc sprues
and quite fast too. i welded the rod of center to the bolt so the vibrator
would not screw the bold out while pouring.
this pic is self explanatory. i'm haveing trouble getting the bullet base
to completly fill and is worst now. i suspect iron contamination from
the pot and ladel. i loaded 5 bullets with the best bases with 14 gr
of unique with 2160 fps av, left target. in the right target same except
i machined the bases flat and true. quite a differance. so if u want to
cast with zinc coat your metal with a ceramic coating and AFAIC
u need a nose pour mould. the bullets look good except the base and a
nose pour would be just the ticket. OBTW i'm in the market for a
44 cal and 357 cal nose pour moulds. pm me please if u have one to sell.
