Need some guidance regarding wrinkled bullets

[mookiie]

My cast bullets have been coming out wrinkled and inconsistent. I am using 1 part lead to 1 part Linotype. I am casting .309 and .312 bullets for rifles. I have a PID I am setting at 725 degrees. I use a bottom pour Lee lead pot. I am using 3 Lee 2 cavity molds and one HM2 5 cavity all aluminum. My current process is to use two molds at a time. Fill them then I let them cool on a metal ledge before water dropping them. While the first two are Colling the next two are sitting on a hot plate. I usually throw the spur excess back in between each pour. I read somewhere that with a bottom pour pot you may need to set alloy temp up to 850 degrees. Can you give me some pointers? Or critique my process?

[Maximumbob54]

Oil in the cavities, mold or pour too cold, or casting too slow which allows the mold to cool too much between pours. Those are my guesses.

[runfiverun]

I'd go with oil or too cold too.
most likely your just flat out running the molds too cold.
use just one at a time and pay attention to what your doing you'll get a lot-more-good boolits that way.
I rarely if ever use 2 molds, I can't count and time things if I'm focusing on something else.

[white eagle]

Sometimes it takes a time or two to season a mold
keep at it it will get better
may also want to try one at a time and forget about mass production

[ukrifleman]

I would go with a cool mould, dunk the bottom edge into the molten alloy for a few seconds to pre-heat the mould.

ukrifleman.

[mookiie]

How hot should the molds be? I have them sitting on a hot plate before pouring. It is probably not oil/grease as I used a degreaser on the molds first. It could be the "break in period" as this was my first time using any of these 4 molds. It could be a flow issue (filling molds to slow) as I was having trouble getting the pour flow regulated. My other concern is temperature of the lead is 725 a good point or do I need to go hotter? Thanks all for the replies!

[ukrifleman]

I use a Lee Production pot 4 and start with the temperature set around 7 to melt the alloy (I don't worry too much about actual temperature readings)

Once the alloy is melted and fluxed I turn the temperature setting down between 5 and 6 and pre-heat the mould by dunking, then I start casting. If the bullets come out wrinkled (too cool) I dunk the mould some more, if they come out frosted I let the mould cool for a little while.

It only takes me a few casts to get the balance right before I get a production run going.

Basically, it's trial and error to begin with.

ukrifleman.

[s mac]

Mould I should be right at a temp that the boolits will be slightly frosted. I agree, your trying to run too many moulds at once. Concentrate on one at a time.

[44man]

Mold is cold, plain and simple.
Do NOT set your filled molds on metal. Use a hunk of hardwood.
A mold only needs to be 500° to make good boolits but you are sucking the life out using metal. By the time you cut and pour again, they are dead.

[williamwaco]

Mold too cold. The sprue puddle should take three to five seconds to solidify.

[plainsman456]

Sounds like to cold.

I like to use 2 molds when doing some runs and once you get the likes and dislikes figured out,things will work.

Don't set them on the plate for long just long enough to empty and fill the other.
If water dropping,drop as soon as sprue is solid.

Keep trying it will happen.

[Larry Gibson]

Moulds are oily
Mould are not kept in a consistent temp range cooling on a metal ledge
different sized moulds cool differently
Not using proper technique for WQ if hardening is the goal

Using too many moulds at the same time for consistent results

Larry Gibson

[Hang Fire]

How hot should the molds be? I have them sitting on a hot plate before pouring. It is probably not oil/grease as I used a degreaser on the molds first. It could be the "break in period" as this was my first time using any of these 4 molds. It could be a flow issue (filling molds to slow) as I was having trouble getting the pour flow regulated. My other concern is temperature of the lead is 725 a good point or do I need to go hotter? Thanks all for the replies!

Ditto on the hot plate, I have a 1/4" aluminum plate sitting on the hot plate and it keeps the mold temps just right for pouring good boolits.

[JeffG]

Temperature wise, I usually heat my molds to about 350 on a hot plate then start pouring the 715-725 alloy. Typically, the very first cast may have a little wrinkle but all the rest will be good. Operating with one mold is a plenty, with counting time in your head and paying attention.


How hot should the molds be? I have them sitting on a hot plate before pouring. It is probably not oil/grease as I used a degreaser on the molds first. It could be the "break in period" as this was my first time using any of these 4 molds. It could be a flow issue (filling molds to slow) as I was having trouble getting the pour flow regulated. My other concern is temperature of the lead is 725 a good point or do I need to go hotter? Thanks all for the replies!

[OnHoPr]

A lot of the above and shaky hands pours.

[gwpercle]

Try casting with one mould. Aluminum moulds don't require a lot of cooling as do iron or brass.
Fill the cavities, when the sprue frosts over, count to 5 and open. Also cast at a temperature just below frosty bullets. Nix the water dropping, fit of bullet to bore is more important, your alloy is plenty hard enough with air cooling. They will get harder in a few days too. I used to believe that harder was better...it's not , softer boolits that fit the bore and a gas check is the ticket.
Load Safe,
Gary

[country gent]

Are you pouring into the mould with a small space between mould and pots spout, or are you fitting the moulds against the spout? As has been said above mould temp is important the metal must remain molten for the complete pour into the cavity and sprue fill. Getting a good fill quickly with a full stream is important. Maybe experiment with the pour some blocks at a slight angle, straight, away from spout, against spout, thru center of sprue hole, and down edge of sprue hole. I dont think temps are to far off but cadence may be on slow side and aluminum disipates heat quickly so you may need to cast even quicker to maintain temps. Start out with one mould casting quick and cast dont look or inspect bullets while casting. Make 25-30 pours then take a few seconds to look at a bullet. If you want to runs 2 moulds you may need to increase temp to 750* for the little extra. Warming or pre heating moulds is a big plus. The trick is to heat them evenly not just one side, edge, or spot but evenly thru out the blocks. Slow even heat works well here. As to breack in you might try heat cycling the moulds 2-3 times before the first casting session. Slowly heat to 400*-500* then let slowly cool to room temp. repeat 2-3 times. This gets the patina on the blocks and readys the blocks for the first session. A good cleaning with solvent then dishsoap and water to remove any residues from the solvent. A light scrubbing with a tooth brush is perfered. Lube handles and joints in blocks lightly and your ready to start.

[rsrocket1]

Agree with the too cool mold. It might make some casters cringe, especially brass or steel mold casters, but I dip my Lee molds in the lead to heat it up. Not from stone cold, but after letting them sit on the edge of the pot as the lead warms up. I dip the far edge from the handles into the lead and pull it out. If the lead "freezes" on the mold or leaves a frozen impression in the melt, I dip it again and again until it no longer sticks to the mold and there is nothing but liquid left behind when I pull the mold out. I then start by casting the bullets and leave a big sprue puddle on the sprue plate to ensure it gets really hot too. I wait at least 6 seconds after the freeze-over before cutting the sprue. Experience will get you the feel as to whether you cut too early and risk smearing lead on the top of the mold, or too late (really tough cut). I use my gloved hand to cut the sprue with a quick twist between my thumb and index finger. That gives me the best feeling of sprue hardness and whether I'm cutting to soon or waiting too long plus it's easier on the mold than whacking it with a stick.

Too hot = frosty = not too bad, still shoot fine
Too cold = wrinkled = not good, may shoot ok, but usually best to dump back into the pot.

[gwpercle]

Agree with the too cool mold. It might make some casters cringe, especially brass or steel mold casters, but I dip my Lee molds in the lead to heat it up. Not from stone cold, but after letting them sit on the edge of the pot as the lead warms up. I dip the far edge from the handles into the lead and pull it out. If the lead "freezes" on the mold or leaves a frozen impression in the melt, I dip it again and again until it no longer sticks to the mold and there is nothing but liquid left behind when I pull the mold out. I then start by casting the bullets and leave a big sprue puddle on the sprue plate to ensure it gets really hot too. I wait at least 6 seconds after the freeze-over before cutting the sprue. Experience will get you the feel as to whether you cut too early and risk smearing lead on the top of the mold, or too late (really tough cut). I use my gloved hand to cut the sprue with a quick twist between my thumb and index finger. That gives me the best feeling of sprue hardness and whether I'm cutting to soon or waiting too long plus it's easier on the mold than whacking it with a stick.

Too hot = frosty = not too bad, still shoot fine
Too cold = wrinkled = not good, may shoot ok, but usually best to dump back into the pot.

Agree with you. I'm a corner dipper also, just follow directions that came with Lee mould for preheating, best method for me.
Gary

[Motor]

Oil in the cavities, mold or pour too cold, or casting too slow which allows the mold to cool too much between pours. Those are my guesses.

Exactly my thoughts too.

Wow!!! 1 to 1 lead/linotype and water quench. Those things must be like 30bhn after aging.

My Lee moulds work best when kept on the warm side. I suggest you start with one mould. Pre heat it some. I usually just let the lead do it by not dropping the first few real quick. Then start casting. You will see the boolits get better and look great then they will start to frost. At that point you found your high limit.

Once your able to keep one mould in the "sweet" spot then go to two. One problem I am learning to deal with using the Lee moulds is the larger the boolits the harder it is to keep the mould in the sweet spot.

Now their new moulds have smaller, trimmed down blocks. My 440gr .501 is nearly impossible to keep in the sweet spot even after I added material to bulk it up which helps.

Motor

[Mike W1]

Spring for a hot plate and use it. Maybe you said you had one but I don't remember. Bought a Lee DC to see if I could learn to cast with it as I'd never had success with Lees in the past. Tried dripping the mould in the melt to heat it up like Lee suggests and by the time that mould would be up to temperature I'd have been in the nursing home. Heated it on the hot plate and good bullets till I got tired of casting.

What's always worked for me are a couple things. You need to get a steady stream out of the bottom. I like about 1/4" between the spout and the sprue plate. Long ago I learned to predict a bad bullet before I opened the mould. Always get my best results pouring into the center of the sprue hole with that continuous stream of lead. I have found if the mould is at temperature that there's no real need for leaving a giant sprue on there either.

I'd definitely go the hot plate route with a Lee. As mentioned earlier the blocks are smaller than they used to be. Thought that was my imagination at first!

I've cast with 2 moulds using Lyman's but were I you I'd stick to one Lee at a time. The problem is keeping the things hot enough and even a hot plate doesn't do as good a job of that as a steady cadence of hot lead.

[mookiie]

Okay, just to give an update what I found my problems were are the following.

1. After the pour I would put the molds on a metal ledge, between pours. This was a mistake once I started laying them on a wood block they retained heat better.

2. Four molds at once is too many. Like many of you said. I switched to using just two molds my results were much better.

3. I found setting the PID at 800 degrees was just the perfect temp.

4. I was using a hotplate, but it was one that had an auto shut-off at a specific temp. I purchased a new one specifically because it did not have that feature.

Now my results are great! I am finding a reject rate of 1 in 20 or so. Before they were more like 1 in 2 were getting rejected, mostly for wrinkles.

[DocSavage]

I just set my blocks on my pot to heat up along with the pot. I only use 1 mold at a time be it aluminum,steel or brass,once hot I have gotten very good looking bullets and weight variation of +/- .5 gr.

[h8dirt]

Make sure the mold blocks are clean and de-greased (HOT water, Dawn and a toothbrush). 725F should be fine for the melt. Bring the mold blocks AND handles to 400F ... And cast away. Keep up a good pace and be careful not to allow the mold to cool below 400F. That is what works for me.

[44man]

I use the little mold oven made from an electric box with a BBQ thermometer in the top. I set to 500° and let them heat soak a long time.
To make matters worse I made my sprue plates from thick stainless so they must get hot but they really hold the heat. The worst plates ever are the Lee.
My blocks are aircraft aluminum and large. My 2 cavities are 1-1/2" wide, 2" long and 1-3/4" deep.
The hardest molds I tried are brass, they seem to give up heat fast.