Casting question

[Tom]

I have a mold that casts an old style minie. The minie shoots really well in my reproduction Model 1855. The old style minies I am familiar with have the level surface at the top of the core pin and are not pointed. When casting with a core pin that has a level surface, I get a large number that are not smooth. Many minies have a “half bubble” or some kind of incongruity where the core pin and the lead meet. Out of 5 cast minies, 1 will be decent but the other 4 are returned to the melt. I still cast with this mold because the rounds shoot so well in the Model 1855. I try to keep the temperature around 850 degrees. I have tried around 775 and above 900 but nothing really changes. I hold the mold at an angle and try to pour the lead in with a ladle doing my best so that the lead doesn’t cover the hole preventing air from escaping.

Is anyone else experiencing the same thing? Do you have any suggestions? Thank you in advance.

[henrymstr]

As far as team competion is concerned blk pwdr is forgiving you prob wont see much change is number of hits. Weigh em out, 10 grns or so you will still break birds. Be more selective for individuals. 10 grns could cost u an X or a ten ring easily. My team rides me for "holy" bullets.......but most have a hard time out shooting me on sunday. Dont get me wrong, they do, but not because of my bullets. I have many other built in excuses at the ready. Good luck, them other fellas will have plenty of tech details when they read ur post.

Sent from my SM-T217S using Tapatalk

[Cannonman1]

used to struggle with my Lyman mold 575213 with the skirts not filing in completely with pure lead. I had an electric pot and ladled the lead out with a dipper.. Tried all sorts of things with little success. I ordered a 20 pound electric pot with the bottom pour feature and my first casting session went very well...Cleaned, dried and preheated the mold and plug as usual, fluxed the lead and began pouring.. By the 3rd cast, I was getting almost perfect rounds and by the 6th or so they were very nice. I am totally sold on this method.. If you are using a dipper, you might want to consider using a bottom pour pot .. I recommend the larger version as you can have a longer casting session with a constant temp. Just my 2 cents worth..
Good Luck

[bobanderson]

I cast on a camp stove converted to propane. I use a bottom pour ladle and pour into the mold straight from the top. Voids are caused by pouring too slowly and the core pin and sprue plate being too cool. I preheat my mold by laying it with the sprue plate close to the burner while I heat the lead to 700 degrees. I cast quickly so the core pin stays hot and rarely get culls, even with the first pour.
BTW - air escapes between the mold and the sprue plate, not the "pour hole."

[John Bly]

The solution to voids in the base at the end of the core pin is to keep molten lead in the sprue hole as the lead cools. The lead shrinks as it cools and if the sprue stays molten it will pull lead into the mold. If you stop the pour and allow the lead in the sprue to cool then the bullet shrinks away from the core pin. You must cast HOT and keep the sprue plate hot so that the sprue is the last to solidify. I bring the ladle and mold to vertical with the ladle in full contact with the sprue plate. I hold it in this position for several seconds to keep a column of molten lead directly over the sprue. I don't get voids this way. Try it. It takes a little practice to get it right.

[Maillemaker]

I used to cast exclusively with a bottom pour pot. I love it for its convenience, and how it avoids all problems with dross floating on top of the melt.

With the RCBS-Hodgdon, you have to hold the mold at an angle and let the lead swirl down the sprue hole or you will get visible voids. But I suspect, based on weight, that the voids might be there anyway even if you don't see them.

There are some hollow-base molds that I simply cannot get without voids / get consistent weights unless I ladle pour.

So I have come to the sad conclusion that you will get the best and most weight-consistent hollow-base bullets by ladle pour casting.

This is why I love the Moose Wilkinson, the Sharps Christmas Tree, and Round Ball - they bottom pour like a dream because there is no hollow cavity.

Steve

[B P Shooter]

I cast with a bottom pour Lee pot. I mold with a 575213OS mold. I have found that when I start having the pinhole problem in the tip of the hollowed out base, it is usually lead sticking to the air holes on the side of the mold as well as the base plug. A bronze or brass brush will usually take it off. Again, that is an issue of air flow.

I know an older member who says it's because the plug is too hot. He swears by dipping the plug into a cup of water when he gets a pinhole. I, personally, didn't care for that idea and never tried it.


What works for one does not always work for another.

[jonk]

If I bottom pour, I get poor skirt fill out.

If I ladle pour, I often get pinholes at the top of the mold plug.

Only with pure lead.

I just consider it part of the process, sort the bullets, and accept I'll get 5-10 rejects on a good day, half the batch on a bad day.

[Cannonman1]

To those who may be reading this line of comment and are planning on doing this for the first time.. or are new to the process.. Make sure you are doing this in a well ventilated zone and wear protective clothing and glove your hands and wear goggles/protective eyewear:cool:.. We all can share those "ouch" moments that are in the learning curve. A little lead splatter on unprotected skin will change your behavior in a heart beat.. just saying

[B P Shooter]

To those who may be reading this line of comment and are planning on doing this for the first time.. or are new to the process.. Make sure you are doing this in a well ventilated zone and wear protective clothing and glove your hands and wear goggles/protective eyewear:cool:.. We all can share those "ouch" moments that are in the learning curve. A little lead splatter on unprotected skin will change your behavior in a heart beat.. just saying

I will add two things to this:
A good pair of leather boots that are not lace-up.

And...well vented area doesn't mean outside in the open. Even if there's not a cloud in the sky. Water and molten lead do not mix. A speck or pindrop of water will cause an hydrogen explosion splattering molten lead everywhere.

[Maillemaker]

A speck or pindrop of water will cause an hydrogen explosion splattering molten lead everywhere.

I don't think hydrogen has anything to do with it, other than being part of what water is made up of. :)

The water is flashing into steam.

Steve

[jonk]

Absolutely the use of protective clothing is good advice for anyone!

The question of ventilation and what is enough... well, you often hear folks talking about 'lead fumes.' That part of it is bunk, at least if you're using an electric melter. They (by design) don't get hot enough to vaporize lead. If you're melting over some other fire source, well, it could get hot enough I guess. But if you're vaporizing lead you are going to need a lot more than being outside to mitigate it. What you do want the ventilation for is that a lot of lead is going to have some contaminants on it. Anything from oil to dirt to whatever. When that heats up it gives off (often a lot of) smoke, and that stuff can't be safe to breathe in. I always took it to mean "do it outside" or "do it near a window with a good exhaust fan pulling the stuff out." Besides... doing it in a basement, making a lot of stinky smoke, is a good way to have your wife/mother/girlfriend/sister/any other female in your life rightly rip you a new one. :D Where I think that material safety IS a good idea is when handling the cold lead. I've seen lead sheet especially with it's large surface area that left a dull lead colored residue on my hands. Lead oxide does wipe off and if you don't wear gloves or scrub your hands quite well, you can get some in your system that way.

The water thing. Yes, absolutely true, moisture and molten lead don't mix. But a little water on top of the melt does... nothing. I started casting long before there were internet forums about this sort of thing, and in my ignorance, when done casting for the day (using a propane torch and ladle) I would gently pour some water on top of the molten lead to harden it faster. Nothing happened, other than the water quickly boiled away. For water to create an issue, you have to get it UNDER the melt. The most likely way someone would do that is with putting a wet or even cold, damp ladle or ingot into a hot molten pot, as just that much surface humidity can cause issue. Or tossing range scrap into a hot pot; inside that minie base is mud, that has enough wetness in it to cause big problems. But to think a single drop of sweat falling from your nose into the pot will cause the tinsel fairy to show up just isn't true. Try to avoid it "just in case" but I'm just saying. It does however, have nothing to do with hydrogen or oxygen, just the rapid expansion of water due to steam formation.

[B P Shooter]

I will politely agree to disagree and move on about the water/hydrogen explosion. Thanks for the input.

[John Holland]

I'm not quite sure where this fits into this discussion about water, but here is my personal experience: About 25-30 years ago I stayed over after the National. I had collected a lot of lead from the backstop and was smelting that salvaged lead at our camp site. I was nearly finished when it started to rain. I had a 20 pound pot ready to ladle out into ingot moulds. My helper grabbed an umbrella and held it over me and the pot to keep the water out of it. Just as I reached out for the first ladle full, the umbrella tipped and the rain water ran off the edge right into the pot. In less than a blink of an eye the entire 20 pounds of molten lead exploded like a volcano! My helper and I both turned our faces fast enough to avoid any burns on them. However, the molten lead went straight up the sleeve of my outstretched arm which was holding the ladle, and burned my arm pretty good. The denim jackets and jeans we were wearing had protected most everything else, except for my helper's hand which had been holding the umbrella. The umbrella itself was coated on the inside with lead, too. My helper's hand was also burned. The pot itself was completely empty of every ounce of the 20 pounds of molten which it had held only a milisecond earlier!

[Maillemaker]

Once I was renting an apartment up in New York, and was trying my hand at tin-plating some chainmail armor. This was before I had discovered black powder shooting. :)

I had a cake pan on the gas stove, and melted some tin in it. I then applied this liquid flux, called "Ruby Fluid", to the maille, and dipped it in the molten tin. Most likely the tin was not very hot and so the tin solidified around the maille and made a solid mess. I decided to re-dip it and leave it in the molten tin to try and let some of the tin re-melt and possibly run off.

So I did this, and suddenly there was an explosion that sounded like a .45 ACP going off! It blasted little tiny bits of tin everywhere. Fortunately it was not very hot and I did not get burned - but there were little tiny bits of tin all over that kitchen. I spent weeks with a plastic knife picking bits of tin off of the ceiling, the walls, the side of the refrigerator, the stove, the floor - you name it.

My guess is that some of that liquid flux was trapped under the initial tin and when I put it back in the pot it flashed into steam.

When casting bullets, I drop into water. I never put bad bullets back into a molten pot for fear of getting water into the melt. But from time to time I have gotten a drop of water in the pot. Most of the time, you get a sizzle or a "pop-spit". My guess is as long as the water sits on top of the melt it will vaporize fairly harmlessly. But if it gets any depth into the lead at all watch out!

Steve