A night of failure…

[lar45]

Might as well ad my .02
Try smoking the cavities with a long BBQ lighter.
Pre heat the mold on a hot plate.
Put an ingot mold under your pour spout, just before you pour the bullets, lift the handle for .5 sec to clear the cold dribble, then pour some bullets.
If you don't get good clean driving bands and sharp corners, take pics of the problem areas and post here.

[justindad]

if your getting stopped up with oxides or other crud in outlet something is real wrong.
ive cast many thousands of bullets with a little lee bottom pour and never have that problem. I think that its because I flux and clean alloy on separate pot and only use real clean ingots in the bottom pour pot. I have had times when I cast ingots and there seemed to be crud in them and I just remelt and flux and strain again.

Until recently, I had been casting with 92-6-2 Pb-Sb-Sn from Missouri Bullet Co. Using their alloy, I’ve always had an issue with oxides accumulating and plugging the nozzle. I also clean this lead is a 4 lb dipper pot before moving it to the bottom pour pot. I’ve always wondered if the MBC lead is kinda dirty.
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So I ordered pure lead from Rotometals and some of their foundry type alloy, so I can mix up 25 lb of clean 96-2-2 alloy (pricey!) and see if anything acts differently.
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I do have suspicions of mold contamination too. I traded here for this thing, and I expect it should be good. Seems I’m the third owner, and it’s definitely not clean on the outside. The inside has water marks and staining that will not clean off with dish soap and water. Might need further action to clean off what could be mold release or other residues.
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Also, my round ball .45ACP casting with this alloy was a success. It did take longer than usual to work out the wrinkles, and wrinkles would come back easily if I slowed my pace (even if bullets were frosted with alloy at 735F), so low tin or contamination are both still possibilities.

[justindad]

I weighed one .45ACP hardball bullet from my WW mix to be 221.6 grains (far left bullet in image below) and with 92-6-2 comes to 225.6 grains. The mold is NOE-454-237-RN. Not sure if the 2% weight difference says anything.
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I got some clean alloy from Rotomolds yesterday, so I’ll see if I get better results this weekend.
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Here’s pictures of some of the better samples that are frosted & wrinkled (one reject kept for this study). I reject when a wrinkle crosses over a driving band, or if about half a driving band is rounded off, or if the nose is wrinkle so bad I could see it breaking off when fired.

[farmbif]

looking at your picture, my bullets look like that until the mold gets hot enough to get good castings. I'd rather have frosted bullets, which are not shiny but look more like oxidized material if that makes sense, from casting a bit on the hot side then wrinkles from casting too cold. to my eyes looking at picture above those look pretty shiny and not frosted. Its possible you just need a bit more heat. sometimes I keep bullets that look like that and load and shoot them but most the time I just remelt them and cast more once everything is good and hot and I'm getting good castings.

[charlie b]

Yep, to me those look too cold.

I judge the temp of my molds mainly from sprue 'freeze' time (full frost over). If it takes less than 5 sec it is too cold. Over 7 sec and too hot. That is with a pretty good puddle on the sprue plate.

I pre-heat the molds on a hot plate. The temp of the hot plate is determined by trial and error. I keep raising the temp until I get good bullets right away. I'd rather have the mold too hot than too cold.

[justindad]

The mold seemed hot enough: the sprue stayed liquid for a few seconds after I pulled the mold away from the valve, and the sprue would fragment when cut. I’ll change two things at once - go with the cleaner lead and cast with the pot at a higher temperature. I also got a thermometer from Rotometals, which tells me the lead is 30F colder than the digital readout, and much farther off as things get colder. I’ll set the pot temp to 780F and see what the clean alloy does… maybe play around 830F just for kicks.
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Can you get frosty boolits with poor fill out if the pot is cold and the mold is hot?

[lightman]

The first thing that I would do is to stop doing so many new things at once. I would quit the 2nd mold to begin with and try to find the "happy spot" with your new pot using just one mold. If you don't get good bullets then you can start tweeking the temps or the alloy. But I would think your alloy would work fine. When you get good bullets you can expand to the 2nd mold. Doing so many new things at once makes it hard to isolate the problem. Good Luck with your new pot!

[Mal Paso]

The stored energy in 780F alloy is not much more than alloy at 700F so raising the alloy temperature will only get you so far. The mold needs to be hot enough that it doesn't cool the alloy too fast.

Most of us are making between 2 and 3 casts a minute not stopping for close inspection. If you need to stop, park the mold on a hot plate, that takes the pressure off.

[rockrat]

I run my lead at about 730 indicated on the lead thermometer, 750 if a brass mould. 96-3-1 is just about what isotope alloy is and I have cast a lot of that stuff. I pre-heat my mould on a hot plate for about 30 min and set it as high as it will go(500 or so) and take the mould and dip the corner in the hot lead for not more than 1 minute, clean it, and start casting. Might get the first pour to have a few wrinkles but most of the time, the boolits are good from the start. I could care less if the boolits look frosty, doesn't bother me.

[dondiego]

I don't see any frosty bullets there. I see bullets that went into a too cold mold.

[Land Owner]

Read about spru plate heating in the King of Casting Manual: http://www.lasc.us/Fryxell_Book_Chap...dleMusings.htm

Search for and read the Chapter entitled, "Heating the Spru Plate". That'll fix this.

[pjh421]

More heat should fix the problem Like the guys said above. If it doesn’t, consider your vent lines. I trace mine with a carbide scribe now and then because they peen over with use and don’t vent quickly enough. This can result in poor fill out.

[justindad]

Last night’s configuration:
1) Rotomolds 94-4-2 alloy
2) NOE-360-160-WFN mold
3) Pot set to 780F (Rotomolds thermometer gives 740F). Close to zero oxides built up on the top of the pot, so I don’t think I overheated the lead.
4) At the moment when each cavity was just full, I would quickly & lightly shake the mold to discourage wrinkles… I think it helped?
5) I believe the mold was hot enough. For some of the night, I had to wait around 10 seconds to cut the sprue to prevent off-center sprues. I did not get any lead wiping across the mold.
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I filled up my table with usable boolits before midnight, which is early for me.
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When the pot thermometer reads 700F, my analog gauge reads 640F. When the pot says 780F, the analog gage says 740F. I think I was casting with cold, dirty alloy, into a dirty mold. The reason I say dirty mold is because I originally had severe sticking, but last night the boolits practically rolled out of the mold (I also cleaned it with brake cleaner and scrubbed out residue the soap-water-toothbrush could not clean).
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I’m pretty sure I still allowed the molten lead to flow too quickly from the nozzle. Gotta improve there.
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Thanks for all your help! I don’t think I would have bought a thermometer without the suggestion.