first bullet alloy cast bullets

[oley55]

A while back I posted some pics of my very first casting attempt with pewter just for fun. I finally got my hands on some COWW (big thanks to Hotrod99) and tried some casting today with 5 different molds. Alloy was COWW with (edit .5% vs 1%) 1% pewter/tin added. Casting temps were 700 and 725, preheated molds on a hotplate to about 350.

Initially I had lots of problems with really wrinkled bullets. Molds were all dual cavity, cast iron and Lee aluminum. I am pretty certain my wrinkled bullets were/are the result of insufficient cleaning/removal of various corrosion preventatives (Birchwood-Casey Barricade or mineral oil). I live on a saltwater marsh and my non-conditioned garage is a haven for rust. I thought if I cast enough times the wrinkled bullets would eventually go away. To some degree they did, but even after 20 cycles there was still some signs of wrinkling.

I am a bit stumped on mold maintenance and storage. If after use you coat to protect your molds, when you prepare to use them it seems like you will have to use such vigorous cleaning methods that any/all careful application of lube at critical points is lost. Is that the process, clean thoroughly and then reapply lube on the alignment pins and etc each time? It was suggested that I just melt a little beeswax into/on the mold while still hot and then let it cool, but won't solvents still have to be used after the beeswax is melted off to prevent wrinkled bullets?

The probability of mold contamination aside, how do these look and what should I be doing differently? Higher temps, a bit more tin, or.....?

[Winger Ed.]

You're on the right path.

All that tin and CCWW is some pretty valuable stuff now days.
For plain base handgun ammo, I use as little of it mixed into pure Lead as I can get away with.

For yours there, I'd shoot most of them, and raise the heat a bit next time.

As far as mold storage,, rust is the enemy.
When mine are cool and empty, I hose them down with spray can motor cycle chain oil.
For long term, after having one get ruined--- I put them in a jar of motor oil.

To clean them, I dunk 'em in a coffee can with gasoline, scrub 'em with a tooth brush, and blow 'em off.
It's the redneck method--- but it works for me.

[P Flados]

Your molds were probably not quite hot enough.

Sometime my molds are a little oily and I start casting anyway. I just crank the heat up on the lead to about 30 degf above my expected good temp. I then start casting and tossing bullets into the reject pile at a fast pace until the mold is hotter than it needs to be. I then adjust the lead temperature down and cast away.

Getting the mold just a little bit too hot at first and running a dozen or so castings is pretty good at burning off any excess oil and getting boolits dropping nice.

[Bazoo]

I reckon you got a bit of contamination and a bit too cold alloy.

For rust prevention, I been using mineral oil. Before I use an iron mould, I generally remove the cutter, wipe all excess oil from the mould and get it dry as I can. Then I color the mould top and sprue cutter bottom, pivot, and alignment pins with a pencil.

I have taken to cleaning the mould cavities with lighter fluid when cold. With or without a toothbrush scrubbing of cavities. Under no circumstances should you toothbrush a hot mould. Then when the mould gets hot, if I have any problems, I open the cutter and fill the cavities with lighter fluid. It doesn't burst into flames like youd expect, rather, it boils in the cavities, scrubbing them.

If I smear lead between the cutter and block tops, I use the pencil to scour the lead off before I drop the bullets.

WW alloy doesn't always make great casts. Sometimes it can be ornery when it comes to fillout or inclusions. Fluxing with beeswax helps it flow better. As does adding more tin. Sometimes I use minimal tin, if I have problems I add more, up to 3%. It will make a difference with an ornery batch of alloy.

[StuBach]

+1 on the bees wax flux of COWW while casting. All the sweeteners (Sb Sn) will begin to separate and oxidize on the top especially the tin. If you flux regularly with a little bees wax it goes a long way to keeping a homogenous alloy through the pot that pours easily.

You can buy beeswax pellets on Amazon in a big bag for a decent price and I’ve found these work great. Just sprinkle a few pellets and some sawdust on top of pot and light it with a match or grill lighter, than mix.


As for storage I coat mine in a light coating of sprue oil (I’m sure any of the options listed above work great too) and store in a locking food snack container with a small desiccant packet (large bag can be bought cheap on Amazon). The container will keep out new moisture and the desiccant will absorb moisture in container. I’m partial to these containers but I get them locally for about $3 a piece Sistema Snack Attack to Go Snack and Dip Container, 1.7 Cup https://smile.amazon.com/dp/B00QC9GN...9W67E9PMSXR11Z (the side compartment works great for pins and what not if mold has them. One of these can store 3 Lyman/ideal 1-2 cavity molds or one four cavity mold with accessories.

When prepping for casting, clean with dish soap and toothbrush while cool. Than throw on hot plate to preheat before casting.

[Thumbcocker]

I put my molds in a steel GI ammo can with a good seal while they are still too hot to touch. They don't rust and no oil contamination.

[centershot]

oley55,
You could have some contamination there, or your mould may be a tad too cool. Ladle casting or bottom pour furnace? If it were me, I'd clean the moulds again using hot water and dishwashing detergent, I like Dawn. Clean with a toothbrush vigorously and rinse thoroughly under really hot water. Especially, rinse under the sprue plate. If your rinse water is hot enough the mould will dry all on it's own but check under the sprue plate to make sure. You can then rinse it in rubbing alcohol if you're not sure you got all the water out. I don't but some do. Once you KNOW the mould is clean you can then adjust temp until your boolits come out good. Frosty-looking boolits are OK, wrinles usually mean the mould is too cool.

As far as storage, your aluminum moulds won't need anything other than protection from being dropped or bumped (impact damage). I keep mine on a shelf in their original boxes, they seem to live there well. My iron moulds get coated with motor oil and sealed in a zip-lock baggie, then they go on the shelf with the others. The aluminum moulds only require pre-heating and re-lubing the next time they're used. The iron moulds must be thoroughly cleaned again before use. This procedure has served me well over the years.

[45-70 Chevroner]

I have been doing this for many years. I clean my molds with dish soap and any kind of cleanser like ajax, or comet. Hot water dish soap and cleanser using a tooth brush vigorously then rinse with hot water while brushing with the tooth brush.

[charlie b]

Haven't had an iron mold in 30 years. Aluminum I just make sure they are clean. The sprue plate and handles may need some rust prevention in very humid climates, but, I'd clean the sprue plate before using. A bit of alcohol will do it. Any mold that has been sitting for a while (months) gets cleaned before use.

For a fresh mold I also like to start out hot and cast a few to get any excess crud out. Using a hot plate to set the molds on works well for this. Then settle down into normal routine and temps.

[oley55]

many thanks guys for your help n suggestions. I put everything I had cast back into my casting pot except for 1 each for measuring/weighing purposes. I imagine having a few more of these trial n error sessions before I consider casting any for purpose. I'm not after absolute perfection, but I know if I don't initially aim high the final results will likely be dismal at best. Next go around I'll probably focus on just one or two molds and stick with same mold material (either cast iron or aluminum) until I start understanding what that material likes or doesn't like.

As for tin usage, yea I was cringing as I dropped 1.25 ounces of pewter tin into what I presumed to be 15 pounds of lead in a Lee 4-20 bottom pour. If or when I work down through the pot, I'll hold off on squandering tin. What is the tell-tell sign that tin is needed?

On the subject of fluxing, as I got up to my PID controlled 725 degrees, I saw where the tin seemed to be trying to separate out. I used either individually or a combination of saw dust and a small dab of beeswax. Pretty sure I do not understand what one or the other is doing. I presume both are burning down into a carbon state that permits the recombining of alloys. Also, after one fluxing I ended up with a really nice black layer across the top. Although I skimmed it off, it just looked like I should have left it there as protection.

I apologize for hitting so many topics, but I have a gazillion observations, ideas and questions rattling around in my 'headset separator'.

[45-70 Chevroner]

For the first 8 or 10 years of casting, I used nothing but straight coww, no tin or pewter. My casting at that time was done at 800 and up to 900 degrees. I think it needed that temp for good fill out. After finding out about tin 700 to 750 is plenty hot enough, although any time I cast 22 boolits I cast at the hottest temp my pot will get. It takes that high heat to keep my six cavity mold hot enough to cast good boolits.

[Bazoo]

Tell tale sign of needing tin is an ornery alloy that doesn't fillout well. Bullets that have a section of full driving band and a section with rounded edges. If all is well you can get 90%+ keepers. I get about 60%-70% keepers from ww alloy with no tin.

More tin makes the sprue cut cleaner instead of tearing, it also makes the bullets change in color slightly from gray to a golden hue when cast side by side. The bases of bullets with minimal tin you can see the grain structure better. Try casting with your alloy and then adding some tin, flux, and then compare the bullets when still hot and you can see the change.

The way I flux when starting my pot with ww alloy is, I use sawdust and let it char. Mix and stir and scrape the pot a good 30 seconds to a minute. Then I skim it and generally I use beeswax and repeat. I do use candle wax but I like beeswax better, it does a better job.

If you're using a bottom pour pot, you don't have to remove the burnt wax or sawdust. It makes a barrier layer and keeps the top of the alloy from oxiding as fast.

[JoeJames]

Per from Ingot to Target, I've been using clean sawdust as a flux on producing ingots from wheelweights. it works well. Did about 5 pounds to day.

[oley55]

Per from Ingot to Target, I've been using clean sawdust as a flux on producing ingots from wheel weights. it works well. Did about 5 pounds to day.

roger that, but my WW are already processed into ingots. I was speaking to fluxing the casting pot vs the smelting pot. Similar processes but I presume with some subtle differences.

[oley55]

OK, I gave it another try and limited myself to playing with just two dual cavity cast iron molds, (RCBS 44-245-kt, Lyman 429215BW). I did not add any additional pewter tin, but gradually upped my casting temps. Gradually moved up from 725 to 750 and then finally 775, although the PID gave me a couple bounces that nearly reached 800 while recovering from my returning cast bullets n sprues. Continued to have wrinkles until I was at or above 775.

As I moved to higher temps I seemed to have problems building a sprue puddle. Lead seemed to want to flow off the sprue plate. I'll assume that's a sign to let the mold cool just a bit, or maybe slow the bottom spout flow rate(?).

I did not go through a serious cleaning regime to start, but I did try the suggested lighter fluid squirted into the hot bullet cavities and that seemed to help a lot.

I am wondering if these look good or if I should consider adding a bit more tin?

Oh yea one other thing with the Lyman mold. The outside cavity wanted to produce fins unless I really put the squeeze on the handle during the pour. I rubbed/cleaned the mold faces with a cotton rag and I looked closely and didn't see anything clinging to either face. Is a tight squeeze fairly normal or do I need to look closer for the cause?

[Bazoo]

Wheel weight ingots can still have plenty of junk in them. I flux a couple times and really go after stirring and scraping when using ww alloy, not counting the initial rendering.

From I got to target is a great resource but I disagree with how great sawdust is for flux. Scientifically it's wonderful I'm sure, but from how the lead acts, beeswax is the best I've found. Beeswax acts different than candle wax. Sawdust is great for an initial flux and cleaning of junk out of alloy. But beeswax makes the lead flow better when casting.

[Bazoo]

Those look real good, especially for ww alloy! If you have to squeeze the mould like that, likely your alignment pin is a touch too far out.

I get the best fillout when I have a large sprue puddle that doesn't overflow the edges or into another cavity. Otherwise I get spot frosting on the sharp edges if a band and incomplete fillout on a band or the base.

[oley55]

Using the same Lyman and RCBS molds I cast about 150 from each. All went well and settled on 775-785 degrees without any additional tin added.

Right up until the very end I kept having problems with the inboard cavity on the RCBS mold with the base not fully filling out. The sprue of that cavity would look sort of bubbly and often didn't quite fill out on the side closest to the sprue plate bolt/pivot point. I am convinced I had some contamination seeping out from around the screw/bolt. Next go around I'll be sure to thoroughly clean under there and probably just use pencil lead for lubrication.

I am feeling pretty dang pleased with myself, and again I want to express my thanks for all the help and advise offered.

[bruce381]

mold is too cold alloy to hot and maybe dirty.

your bullets look good tho.

try 700 and let pot set a bit any crud will float to top.

put mold into alloy and let set a few minutes, I cast with a hot mold and get a slight frost on bullet and they fill out 100%
again your mold is too cool.

Running pot at 770 will cause a lot faster oxidation of tin etc too hot I think.

[WHITETAIL]

Welcome to the forum oley55.
And I would say that the advice given here
is spot on.
The way I keep my molds is sprayed with WD-40
in a Zip Lock bag and put on the shelf till needed.
Then I take it out in the back yard and spray it
with Carb cleaner over a open trash can.
Then give it a small shake off.
I have been doing this for 30+ years and having
good results with no rusting or oil problems when
making my boolits.