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BOOM BOOM
02-06-2010, 05:51 PM
HI,
Has anyone cast Zn bullets?
Does anyone have any information , new or old , on casting with Zn ?

leadman
02-07-2010, 12:37 AM
......

Daddyfixit
02-07-2010, 03:45 AM
I have an old soft cover book with an article on casting zinc rifle bullets. I you PM me you e-mail address I'll try to scan it for you.

I have access to a lot of zink, This would be of intrest to me also

randyrat
02-07-2010, 08:41 AM
Seems to me you could cast undrsize and paper patch. Someone around here does just that with great results. Check the Paper patch threads.
You would have to cast it good N hot.

randyrat
02-07-2010, 08:46 AM
I have access to a lot of zink, This would be of intrest to me also
Zink is high on the markets just like lead. Zink is great for the BIG BORE guys, like Cannon balls. they can use them over and over.

sagamore-one
02-07-2010, 09:18 AM
I quit trying to cast with Zink years ago. Not that it can't be done, it kinda was hard on the equipment. If I remember correctly , it took very high temp ( 900 plus) of both the mould and the melt (alloy) to get decent bullets. All equipment needed to be extremely clean, melt well fluxed, and rate of casting really fast to keep the mould up to temp. Finished bullets were quite a bit lighter in weight than regular lead alloy boolits, but shot just fine. I,m thinking that the H&G 68 ,200gr came out around 165 gr.
Got tired of the drama.

The Double D
02-07-2010, 10:41 AM
I have access to a lot of zink, This would be of intrest to me also

Do you share?

chris in va
02-08-2010, 02:28 AM
We'll all be casting zinc in a few years. Or compressed/powdered iron.

BOOM BOOM
02-09-2010, 07:41 PM
HI,
Most of what I found was in an old copy of CARTRIGES OF THE WORLD.
Zn makes very hard & very light bullets. It was done by a lot of casters pre 1950's.
Also bullets were cast to accept Zn washers like gas checks. These Zn checks worked.
I found no info on tech. or how to do it.
Mixing Zn & Pb is a disaster.
But you can dilute the Zn to a low enough level (with a lot of Pb) so you can cast good bullets. You can also remelt slowly W/ carefull temp. control & scrape the Zn off the top.
My impression is that It may be best to have a melting pot decated to doing only Zn.:Fire::Fire:

BOOM BOOM
02-11-2010, 07:55 PM
HI
Another thought, all the pre 1950 casters were probibly using iron molds.
This might not be a good to try in an alum. type mould. high temp. might be bad, & as the bullets were reported to be very hard, cutting the sprue might damage a Alum. type mould.

BOOM BOOM
02-16-2010, 07:44 PM
HI,
With the dissapearence of Pb ww, by 2012.
The huge amounts of Zn ww we are finding.
More places outlawing Pb (ranges,hunting places) the eco-nuts seem to be winning.
Zn could be an option .
I found this info:

Zn-melt pt.- 787 *F
Mohns Hardness= 2.5
Brinell " =412

Pb- melt Pt.=621* F
Mohns hardness=1.5
Brinell " = 38.3

Cu-mely pt.=1984*F
Mohns hardness=3
Brinell " =874

Al-melt pt.=1220* f
Mohns hardness=2.7
Brenell " =245

So Zn is about 1/2 as hard as Cu jackes, but it's hardness is so close to Al I would not recommend using Al moulds.

Al-moulds would not be hurt by the heat.

sagacious
02-16-2010, 09:30 PM
HI
Another thought, all the pre 1950 casters were probibly using iron molds.
This might not be a good to try in an alum. type mould. high temp. might be bad, & as the bullets were reported to be very hard, cutting the sprue might damage a Alum. type mould.
I used to cast a lot of zinc bullets. I just sized and lubed with a wax lube, and used a target-level or midrange load for the as-cast weight. Works fine. I also used to pour a lot of zinc for other purposes, so I had a lot of experience with pouring zinc and had little difficulty. Like the commercial says-- your results may vary.

This is definitely a job for an iron mold. The melting point of aluminum has nothing to do with it. An aluminum mold with an aluminum sprue plate would almost surely be damaged severely quite soon-- not to mention the fact that zinc will readily stick to bare aluminum. In fact, molten zinc will aggressively and rapidly dissolve aluminum even though aluminum melts at a higher temp. The best way to start is to use well-fluxed zinc and a large caliber one-or two cavity mold, such as 44 or 45cal.

Anyone who attempts this should note that even the smallest splashed droplet of zinc will burn you such that you remember it for a very long time. All safety precautions must be observed strictly when working with molten zinc.

Best of luck! :drinks:

leftiye
02-17-2010, 03:01 AM
Now, the vapors fron zinc ARE muy bad! Makes lead seem neutral by comparison. Don't breathe them unless the alternative is lethal! All velderz know this.;)

But Paul is right, If we have to, we can make cast zinc boolits. I don't plan to have to though.

qajaq59
02-17-2010, 07:59 AM
Zinc must be real tough on the sprue cutters as well. That's a pretty hard material.

BOOM BOOM
02-17-2010, 08:03 PM
HI,
Found out HANLOADERS DIGEST #12 has an artical, I don't have acess to it , but am tring to find one. Also there is suppost to be an old article in the AMERICAN RIFLEMAN as well. Am trying to find it too.

The bullets are suppost to wiegh 60-63% of what the mould casts Pb bullets at.
Zn bullets clean lead from the bore.
Zn bullets do not require lubing, or gas checks.
They can not be sized in regular lude sizers.

MJR007
02-17-2010, 08:25 PM
I have plated a lot of zinc dicast. It is very easy to screw up.

docone31
02-17-2010, 08:27 PM
I use a remarkably high percentage of zinc in my castings. So far, so good.
I paper patch also.
I have yet to cast with pure zinc, but I can see it in my future.
I also have that article.

sagacious
02-18-2010, 02:12 AM
Now, the vapors fron zinc ARE muy bad! Makes lead seem neutral by comparison. Don't breathe them unless the alternative is lethal! All velderz know this.;)

Note that welding galvanized steel will actually burn the zinc and vaporize it. A similar risk is posed when alloying copper and zinc to form brass. If you've ever worked in a brass forge, you're seen that green/blue/whitish flame of burning zinc. That is the source of risk for 'metal fume fever.'

Simply heating and pouring zinc at normal casting temps does not expose one to risk of metal fume fever from volatilized zinc. As safe as, or safer than, pouring lead. Burning (vaporizing) lead runs similar or worse risks of toxicity, but lead kept at 'normal' pouring temps poses little risk of exposure to toxic vapors.

Just shining a little light on it. Keep on keepin on! :drinks:

leftiye
02-18-2010, 03:38 AM
Sagacious, I kinda guessed that. One should be on the lookout for metal vapors, and aware that they are poisonous.

It sounds like a bore riding design with no grooves, and a driving band at the base, or a tapered straight wall boolit cast from zinc would maybe work quite well. (seat the driving band only in the case maybe, chamber the rest in the bore. Would chamber nicely in those wierd Marlin and H&R 45-70 chambers). A mold could be simply bored (no cherrying or self centering vise needed) into a block or set of blocks.

uscra112
02-18-2010, 08:32 PM
Col. Harrison did a little testing many years ago. As I recall, he didn't think much of them.

dominicfortune00
02-18-2010, 10:35 PM
Also bullets were cast to accept Zn washers like gas checks. These Zn checks worked.
I found no info on tech. or how to do it.

The molds you speak of are known as Lyman molds marked Harvey Protex Bore.

The idea was to place a specially sized zinc washer in the special mold half, close the mold, and cast a boolit with a built in zinc gas check.

Occasionally on ebay I see one in .38 with a supply of zinc washers come up for auction.

These were only seen in pistol calibers.

Lloyd Smale
02-19-2010, 08:18 AM
I did some years ago. I made some good bullets but they were almost half the weight of lead and very brittle so they werent practical for much and clean up of the molds and pot was a bugger. They worked real well for cleaning the lead out of barrels though.

BOOM BOOM
02-22-2010, 08:25 PM
HI,
FOUND THIS:
GOOD CASTING ALLOYS OF ZN ARE ZAMAK/ZAMAC. But there are 12 diff. versions.
Kirksite or zamak #2 has more Cu. In europe Zamac is called Mazak (made with a slightly different process).
all 12 alloys are mixes of Zn, Cu, Mg, &Al.
They can be fluxed by Salicytic acid (asprin). Do not need a lot of fluxing.
Also .001"undersized bullets work well, some have mentioned a warning about oversized bullet being a pressure problem.
I wounder about this Zn is ductile, & is only 1/2 as hard as Cu jacked bullets, and 2x's as hard as Pb on the mohs scale (measures resistance to scratching, or in our useage engriving into the rifling).
1 source mentions that you want to remove all Cu fouling before shooting Zn, for acc. reasons.
May have to run alloy temp. to cast about 50* higher then melt temp. for good results. This means about 800-850*.
Also avoid higher temp. as alloy will pick up Fe from pot.
Need spru holes25-50% bigger than for Pb casting.
Don't let Spru completly harden as cutting gets VERY DIFFICULT.
Don't roll crimp or use a heavy crimp as bullets tend to fracture, THEY ARE BRITTLE.
And will fracture along plane of the crimp.
Will try to find more & post it.

BOOM BOOM
03-05-2010, 07:21 PM
HI,
Found some more info:
The people who did it found them to be accurate.
There were lower pressures than jacked, 0 bore fouling.
More brittle than Pb, but as were much lighter than same cast bullet in Pb, the same load gave higer vel.
Or could load to same vel., with much less recoil.
The lower sectional den. led to less penatration.
Impact was diff. than both Pb or jacked bullets.
Needed faster burning powder as bullets were so much lighter.
You want to preheat the mould to at least 400 degrees F.
you want to use the lowest temp. you can to get good bullets as higher temp. leads tocracks & poreosity. And the Zn will pick up Fe from the pot.

I think from what I could glean from the metilurgical engeneering sites that we want to get hypoeutectic alloys with less Al than 4%, & less Fe than 1%. so Zamak 2 might be best. It is used in gravity casting.
Zamak 3 is used in die casting, Zamak & is lower in Mg to increase fluidity of the alloy so it might be a good canadate too.

IF YE ARE PREPAIRED, YE SHALL NOT FEAR. D&C 38:30:Fire::Fire:

sagacious
03-05-2010, 08:26 PM
All Zamac alloys are much harder than pure zinc. Sprue cutting can be a real chore with Zamac.

Super hard is not what you want. Just scoot down to the local marine supply and buy a pure zinc anode in the size/weight you want. Anode zinc is easy to work with.

There's no secret trick to it, just melt the zinc and pour. Gotta keep the mold hot, but correct heat management is part of the process with both lead and zinc.

BOOM BOOM
03-06-2010, 05:20 PM
HI,
Does anyone know what the Zn tire wts. are made of??????????????????
Pure Zn or Zamak ????????????
They would be free. That why I started thinking of this.

They that plow iniquity , and sow wickedness shall reap the same.
Job 4:8

I found out that Hillery Clinton was a big force behind the lead ban. She was pushing this in 1993 when she was 1st lady. My source on this was Jeff Coopers commintaries. Then she was not suppost to have much if any power, she was suppost to be just a figerhead. NOW SHE HAS REAL POWER AS SEC. OF STATE !
YIKES!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Tom-ADC
03-06-2010, 05:35 PM
I tried some Kirksite years ago, mostly zinc, but weight was off and IIRC they were famous as flyers, we gave up on them.

BOOM BOOM
03-30-2010, 02:45 PM
HI,
The wt. of the Zn bullets should be close to 65% of the Pb bullets. So w/ the same load POI should be lower, I believe.

ghh3rd
03-30-2010, 05:04 PM
Has anyone cast Zn bullets?
Not intentionally [smilie=1:

Multigunner
03-30-2010, 05:24 PM
Note that welding galvanized steel will actually burn the zinc and vaporize it. A similar risk is posed when alloying copper and zinc to form brass. If you've ever worked in a brass forge, you're seen that green/blue/whitish flame of burning zinc. That is the source of risk for 'metal fume fever.'

Simply heating and pouring zinc at normal casting temps does not expose one to risk of metal fume fever from volatilized zinc. As safe as, or safer than, pouring lead. Burning (vaporizing) lead runs similar or worse risks of toxicity, but lead kept at 'normal' pouring temps poses little risk of exposure to toxic vapors.

Just shining a little light on it. Keep on keepin on! :drinks:

Cadmium is said to be extremely toxic, and ship board welders and salvage workers have died from cutting or welding cadmium plated steel without knowing it.

Zamak is tough enough that some pocket pistol frames have been cast from it.

Zinc alloy bullets were used to test armor plating, due to its consistent performance.

If a zinc alloy bullet is cast in a mold previously used for lead a catalytic process from surface contamination can cause the bullet to crumble months later. If casting zinc its best to use only a new mold and use that mold only for zinc.

During the US Civil War paper cartridges loaded with slugs with a zinc base were issued for scraping out leading of rifled musket bores.

sheepdog
03-30-2010, 05:37 PM
We'll all be casting zinc in a few years. Or compressed/powdered iron.

Negative. Those of use that hoard lead and reclaim our own shot will more than likely make it til the jackboots come door to door for the last great grab.

sagacious
03-30-2010, 06:38 PM
If a zinc alloy bullet is cast in a mold previously used for lead a catalytic process from surface contamination can cause the bullet to crumble months later. If casting zinc its best to use only a new mold and use that mold only for zinc.
It would be interesting to read the source material, or some confirmation of the above statement.

I have zinc bullets cast many years ago, and they're still as as shiny and solid as they day they were cast--
in some very old Lyman 45ACP molds previously used with lead.

docone31
03-30-2010, 06:55 PM
Zinc casting is ok. Takes a world of heat and cutting the sprue is harder. I use Lee sizeing dies.
I use them in paper patching. So far, so good. There is an article floating around on casting with zinc.
I have found, the trick, is to add lead to zinc. When I have alloyed and added zinc, it made oatmeal. When I have added zinc, it made a mess.
It takes high temp, and a good stir and flux. 2% zinc to lead is ok. Going the other way up to 10%lead to zinc. Over that and you get oatmeal.
I have had decent results. Sizing is different. I size .357 for the .357 loads, .309 for .308 loads. It is harder so it does not flow into the bore easily.
fires well though.

MtGun44
03-30-2010, 07:46 PM
I have an old NRA book with a short blurb. Mentions using Zamack #3 and having
good results with zero bore 'zincing', good accy and no need for lube, IIRC. Won't be
home where I can find it for a few days, will try to remember to find it and scan and
post. Not a big article, maybe 100 -150 words, but pretty dense with facts and numbers.

PM me in a couple days if you are interested.

Firebricker
03-30-2010, 07:57 PM
Boom, I have an old Handloader Mag with a good article on casting zinc boolits. If I can find it I'll try to scan it and send you a copy if you have'nt got anything in print yet. FB

BOOM BOOM
03-31-2010, 03:37 PM
HI,
All the stuff I have , is just vague references to casting bullets .
All the other stuff I have posted is from metallurgy or engineering sits.
I have found several references to articles on casting Zn bullets, but have not been able to get a copy of any of them to read.

I have gathered all the Pb I could get around here, & also now have a steel bullet trap. So I am doing what I can to keep a Pb supply.
But even with those conservation efforts, I can see a possibility of running out of Pb.

So with a free source of Zn tire wts. I am exploring the Zn bullet option as an alternative.
I would appreciate it, if any of you have the articles, please post them here or scan & send them to me. I would not be able to scan them or post them as I am NOT a computer wizard.:Fire::Fire:

sheepdog
03-31-2010, 03:49 PM
Casting zinc is not going to make you popular with berm farmers. Not one bit.

BOOM BOOM
03-31-2010, 03:54 PM
HI,
It is not that I want to, it may end up being the only way I can afford to shoot!!!!!!:Fire::Fire:

The Double D
03-31-2010, 06:46 PM
HI,

All the other stuff I have posted is from metallurgy or engineering sits.


:Fire::Fire:

Can you share the links to those sites?

Jaybird62
03-31-2010, 11:36 PM
Since it has been mentioned that Zn leaves no residue and it was used to clean lead from bores, could Zn bullets be used to "clean" leading out of a bore? When I head to my range to experiment with different alloys and loads, I usually get a few that want to lead the bore. It would be nice to fire a Zn bullet and start fresh instead of spending a lot of time scrubbing lead fouling from the bore.

BOOM BOOM
04-01-2010, 07:47 PM
HI,
Yes they have been reported to clean lead out of leaded bores.:Fire::Fire:

Firebricker
04-02-2010, 10:39 PM
Boom, I just found the article I mentioned earlier. It's in Handloader #71 zinc for police load's.
PM me your adress and I'll have it scanned and mail it. FB

Bkid
04-02-2010, 11:04 PM
Can you use Aliminum in a gun barrel. I have a silver foundry and casting shop, and have cast aluminum before. I could cast a ton of aluminum bullets.

sagacious
04-02-2010, 11:50 PM
Can you use Aliminum in a gun barrel. I have a silver foundry and casting shop, and have cast aluminum before. I could cast a ton of aluminum bullets.
Yes, it's been done. For close-range target use it's OK.

As you know, gravity pouring of small aluminum castings can be very frustrating. Pouring small zinc castings is a snap, as compared with aluminum. My experience is that adding a small amount of silicon to the alloy greatly enhances the 'pourability' of aluminum. Good luck.

Bkid
04-03-2010, 12:02 AM
Yes, it's been done. For close-range target use it's OK.

As you know, gravity pouring of small aluminum castings can be very frustrating. Pouring small zinc castings is a snap, as compared with aluminum. My experience is that adding a small amount of silicon to the alloy greatly enhances the 'pourability' of aluminum. Good luck.

I have a vacume caster wich works great with casting aluminum. Do you have to lube aluminum boolits?

sagacious
04-03-2010, 12:27 AM
I have a vacume caster wich works great with casting aluminum. Do you have to lube aluminum boolits?

Sounds good. You might wish to give it a go. Free scrap aluminum is easy to find. Extruded aluminum alloys especially need some silicon added.

I doubt that you have to lube aluminum bullets. But you may want to (may need to) size the bullets.

I just size and lube both zinc and aluminum bullets with a standard wax lube during sizing-- whether they actually need it or not, on the theory that a little lube is a good thing. If you don't have a lubrisizer, you can use a LEE die and Alox. Or, you can skip the lube and see how it works for you.

DLCTEX
04-03-2010, 06:21 AM
You wouldn't want to use a Lee mould casting aluminum boolits., would you?:mrgreen:

BOOM BOOM
04-04-2010, 12:14 PM
HI,
DO NOT USE Al MOLDS IN CASTING Al, OR Zn!!!!!!!
Ruins mold.
Also you would need to shoot the Al bullets as soon as possible, as Al oxide is VERY ABRASIVE,

BOOM BOOM
04-04-2010, 12:30 PM
HI,
KEN MOLLOHAN has an article on los angeles sil. club site.
Zamak on Wikipedia.
Ritchey Metals site.
SHOOTING ZINC IN BIG BORES, BY KARL BOSSELMAN MY BE in 9th edition of Handloaders digest p128---I do not have a readable copy of this & if anyone does please send me a copy. But I know it exists.
Lead free Wheel weight: All tire co. site.
Nuclead site.
I looked at dozens of others but only printed out these sites as they were the best.

Bkid
04-04-2010, 02:22 PM
You wouldn't want to use a Lee mould casting aluminum boolits., would you?:mrgreen:

No I would use a lost wax process used in jewlery casting.

sagacious
04-04-2010, 08:33 PM
HI,
DO NOT USE Al MOLDS IN CASTING Al, OR Zn!!!!!!!
Ruins mold.
Of course not. That's been covered repeatedly. Use an iron mold.


Also you would need to shoot the Al bullets as soon as possible, as Al oxide is VERY ABRASIVE,
Aluminum bullets are not abrasive. Aluminum oxide forms virtually instantly, and is so vanishingly thin that it's almost not even there, so time is certainly not of the essence, and abrasion is no concern. This myth has been dispelled before, too.

The only concern is keeping your Al bullets clean, as most know that it's the grit embedded in an Al cleaning rod that presents a wear problem, and not the Al itself... but then one must also keep his lead bullets free of grit as well. Not a problem.

Good shooting. :drinks:

Bkid
04-04-2010, 08:46 PM
When casting most metals ,keeping it clean, and temp are the keys to sucess.

BOOM BOOM
04-06-2010, 06:10 PM
HI,
Sorry, I was answering a posted question 1-2 posts earlier on the moulds.
I just threw in the comment on AlO3 as an abrasive, did not know it had been discussed. Did not see it on this tread anyway.
Where was it discussed?????
I would like to read it.
Perhaps I have shied away from the Al gas checks unnessacarily.:groner:

sagacious
04-06-2010, 07:30 PM
HI,
Sorry, I was answering a posted question 1-2 posts earlier on the moulds.
I just threw in the comment on AlO3 as an abrasive, did not know it had been discussed. Did not see it on this tread anyway.
Where was it discussed?????
I would like to read it.
Perhaps I have shied away from the Al gas checks unnessacarily.:groner:

BB,
No worries, no apology necessary. And I hope my comments did not seem... abrasive lol! :)

If you do a search for "aluminum+oxide" I reckon you should turn up some threads/discussions on the forums here.

Briefly, the question about Al2O3 abrasion from the use of aluminum jackets/bullets/gc's/etc, is a valid one. It's an understandable concern. The short version of the response to this concern is that the Al2O3 is such a vanishingly, unbelievably, increadibly thin layer that it's almost not even there. The Al2O3 forms almost instantly, but once a super-thin layer forms, it prevents any more Al2O3 from forming... so the layer stays atomically thin. A thicker layer of Al2O3 usually requires that the Al be treated with electricity and/or oxidizing acids, which are not a factor in home casting and reloading. It will not build up like the Al2O3 on sandpaper.

Realistically, the dust that falls on a box of loaded cartridges offers about the same level of abrasion-- so one need not worry about abrasion or barrel wear from Al gas checks. If you can get into Al gc's inexpensively, you might wish to take another look at it.

Hope this helps, and as always-- best of luck! :drinks:

jbunny
04-06-2010, 08:22 PM
Sounds good. You might wish to give it a go. Free scrap aluminum is easy to find. Extruded aluminum alloys especially need some silicon added.

I doubt that you have to lube aluminum bullets. But you may want to (may need to) size the bullets.

I just size and lube both zinc and aluminum bullets with a standard wax lube during sizing-- whether they actually need it or not, on the theory that a little lube is a good thing. If you don't have a lubrisizer, you can use a LEE die and Alox. Or, you can skip the lube and see how it works for you.
zinc has good lubercity, no lube needed. in my experiance with aluminum
pistons in steel cylinders is when it scuffs it welds itself to the bore and acid or
fine sand paper is needed to remove.
jb

dangerranger
04-10-2010, 03:19 AM
so if I wanted a 224 bullit for a 1/12 223 or 22 hornet out of zinc, Id have to start with a 55 or 60 gr iron mould. pour hot. and alloy with a little tin? and Ill get a bullit weight of 35gr? I live in the lead ban area of CA and want to find an inexpencive varmit round. or would I be better off pouring from tin solder? I get about a 1lb can of scrap solder every other mo. DR

jbunny
04-10-2010, 04:24 AM
i use straight zinc. tin will alloy with zinc and and make this alloy stick
to the ladle. that has been my experiance. YMMV
JB

DLCTEX
04-10-2010, 07:04 AM
Zinc will ruin aluminum moulds? I don't know about pure zinc, but I've cast boolits with a lot of zinc in the alloy and Lee moulds with no ill effects to the pot or mould. The high temps needed to cast pure zinc may be harmful to aluminum, but I haven't seen it. I cast with some pretty hot Lee moulds when casting big bore boolits.

BOOM BOOM
04-10-2010, 04:18 PM
HI,
According to my research, (I have not started to cast yet) use only the iron molds.
This is with pure Zn.

sagacious
04-10-2010, 08:28 PM
Zinc will ruin aluminum moulds? I don't know about pure zinc, but I've cast boolits with a lot of zinc in the alloy and Lee moulds with no ill effects to the pot or mould. The high temps needed to cast pure zinc may be harmful to aluminum, but I haven't seen it. I cast with some pretty hot Lee moulds when casting big bore boolits.
Pure zinc is a lot harder. That put considerably more stress on the mold.

Those new to pouring zinc should be advised that one and 2-cavity LEE molds use a steel sprue, whereas the 6-cavity LEE molds use an aluminum sprue plate. The rub is that plenty of people have broken the aluminum sprue plates using lead alloys. If one uses a 6-cavity mold to pour zinc, the risk of a broken sprue and damaged cavity edges goes through the roof.

The safest and best practice to recommend generally is to use a steel mold with a steel sprue plate. If one uses an aluminum mold, the potential for mold damage exists, so use a mold that you're not worried about damaging.

Best of luck. :drinks:

sagacious
04-10-2010, 08:42 PM
so if I wanted a 224 bullit for a 1/12 223 or 22 hornet out of zinc, Id have to start with a 55 or 60 gr iron mould. pour hot. and alloy with a little tin? and Ill get a bullit weight of 35gr? I live in the lead ban area of CA and want to find an inexpencive varmit round. or would I be better off pouring from tin solder? I get about a 1lb can of scrap solder every other mo. DR

Tin solder would be much easier to start out with. I'd recommend that you take that route first and see what your results are. My experience is that small-caliber bullets are more difficult to pour with zinc than the larger-caliber bullets, but you may be able to make it work for you.

Good luck.

sagacious
04-10-2010, 08:57 PM
zinc has good lubercity, no lube needed. in my experiance with aluminum
pistons in steel cylinders is when it scuffs it welds itself to the bore and acid or
fine sand paper is needed to remove.
jb
Good observation. Lubricity may be a factor of alloy composition here-- in the same way that pure copper usually leaves more fouling than copper with a bit of zinc (bullet jacket alloy aka gliding metal). I always added a few percent Cu to the Al, and that might make the difference that leaves no fouling-- but I also always lube both Zn and Al just in case.

Good shooting. :drinks:

dangerranger
04-11-2010, 01:04 AM
Tin solder would be much easier to start out with. I'd recommend that you take that route first and see what your results are. My experience is that small-caliber bullets are more difficult to pour with zinc than the larger-caliber bullets, but you may be able to make it work for you.

Good luck.


Well Im ready to give it a shot, I have a few lbs of both tin solder and zinc wheel weights Ill let you all know how it goes. DR

Multigunner
04-11-2010, 01:19 AM
It would be interesting to read the source material, or some confirmation of the above statement.

I have zinc bullets cast many years ago, and they're still as as shiny and solid as they day they were cast--
in some very old Lyman 45ACP molds previously used with lead.

From scientific American volume 248

The most important metallurgical precaution to be observed in melting Kirksite "A" is that contamination by lead and tin must be avoided. One half of 1 percent of lead will reduce the tensile strength 30 percent and the impact strength 75 percent in one year of normal aging, and will also cause the dies to expand 1/8 inch per foot in the same period. More than 1/4 percent iron is also harmful, causing

surface defects in use, known as "dural-bug marks"

http://books.google.com/books?id=AXgPAAAAIAAJ&pg=PA370&lpg=PA370&dq=Lead++kirksite&source=bl&ots=y2b2vK93lw&sig=V0VmCMMbNTqX3ILsHTLR6yyGlMA&hl=en&ei=Z1rBS5mfEMGblgefv4nbBA&sa=X&oi=book_result&ct=result&resnum=6&ved=0CBcQ6AEwBQ

There are other admonitions against exposing Kirksite Zinc based Bullet Alloys to lead.
I'll see what I can find.
If your mold stays very clean you probably aren't exposing the alloy to enough contamination to cause harm.

Found this
The content of Kirksite Alloy


Zinc - remainder
Aluminum - 3.5% to 4.5%
Copper - 2.5% to 3.5%
Magnesium - 0.02% to 0.10%
Iron - .20% max
Tin - .01% max
Lead - .02% max
Cadmium - .015% max



With .02% in the alloy already it would not take much lead residue in a pot, dipper, or mold, to contaminate the surface to the .05% danger zone.

sagacious
04-11-2010, 01:50 AM
From scientific American volume 248

There are other admonitions against exposing Kirksite Zinc based Bullet Alloys to lead.
I'll see what I can find.
If your mold stays very clean you probably aren't exposing the alloy to enough contamination to cause harm.
Multigunner,
Thank you for the link to the SA article. I read it with interest. By coincidence, I use some Zamak alloys to make dies for forming brass into pre-draw forms for some of my bullet swaging projects. For use with annealed 70/30 brass and a steel punch, the durability of the Zamac dies is plenty adequate.

It may be exactly as you surmise, that a clean mold poses little risk of contamination. I have always poured with pure zinc (anode zinc), and so minor alloy 'contamination' may not present the pure-zinc caster with as much of a concern. Even so, I do not and would not use my lead melting pots, etc, for melting zinc. Zinc and zinc alloys get their own crucibles and casting pots.

The basis of my interest in this detail of this subject is that several Zamac alloys contain a fraction of a percent of Sn, Pb, and Fe as well. Although none that I am aware of contain as much as the 1/4 percent Fe as cautioned against in the article, it was enough of a relation to catch my notice. I hope you see where I'm coming from.

I think we are often spoiled with the Pb/Sn/Sb triad, as it's various alloys are not rendered useless by small changes within that triad. For that, we are quite fortunate. Many other alloys are not so forgiving.

Thanks again, and good shooting. :drinks:

shotman
04-11-2010, 02:43 AM
dont use the Aluminum molds you are going to have problems with pins getting loose