I think I solved my problem, but ...

[Wayne Smith]

I got a new Lyman 457122 Gould hollow point mold and cleaned it and started casting. I'm using a cast iron pot, 2 burner Coleman stove, a Lyman ladel, and 50/50 (ww/Pb) approximate metal. I got a number of good boolits (around 20) once it heated up, maybe five or so boolits to heat it up. My temps were up around 830 so I cooled it a little. From one great boolit to the next I had almost 1/3 incomplete fill on the base. I continued to cast and continued to get poor bases. I checked my temp and was down to 750. I thought it should cast at that temp, cleaned the top of the mold, applied BullPlate to it, and still got incomplete fillout. Finally I got one that didn't even complete the boolit, I knew I was too cold.

I upped the heat and didn't get a good boolit until I hit 817 degrees! From then on it cast fine with no problem as long as I kept it around 830. I have just never had a mold that required this much heat.

I'm using one of the Chinese electronic thermometers so my temps ought to be accurate. It is accurate for air temp.

[DLCTEX]

Have you had good results with this same alloy in other molds. It sounds as if you may have zinc contamination. If so, running the higher temps will produce good boolits IMHO. DALE

[runfiverun]

no fillout and have to run above the melt point of zinc to get good boolits..
you either got zinc contamination.
or you really need some tin..

[Sig shooter]

Try a quicker pour , or tin . Your not doing the speed casting with a wet rag to cool it / casting at higher temps ? I bet your cooling a bit with the pour temp at 770 -750 out of the ladle .

[docone31]

That does sound like zinc. My pot did the same thing untill it stopped pouring.
I had at first been casting at around 8, or 9, on the Lee 20lb bottom pour pot. Upon reading some of these threads I turned it down slowly.
I got some oatmeal on top and the bottom pour trickled to an halt. I tried using a pin to open the spout, but it did not pour.
I finally decided I had zinc in the melt so I fluxed it, turned it up and let it sit for a bit.
I then turned it down slowly untill the oatmeal became thick. I lifted it out, fluxed, stirred, added 50/50 about 3" of a bar, and let it sit. A little more floated to the top, I lifted it out, and a-pouring I went. I did not have issues after that. I also, now run back at #8 for my pours.
Sounds like zinc.

[NoDakJak]

docone31 That sounds just about identical to a problem that I had about a month ago. I was just a little angerfied and the air was blue! Finally got so pixxed off that I yanked the plug. As I was cleaning up I noticed a rather sludgy mass in the middle of the pot as it cooled. I spooned it out fairly easily. Was roughly the shape of a very soggy ball. I evidently did not get it all out as I am having to run the pot very hot and the boolits have that oatmeal texture. They seem to shoot fine though. Incidentally, I finally recieved my new RCBS Pro Pot last week and have run about a thousand boolits through it so far. Whaat a joy it is after using the Lee pots since they first came on the market. Neil

[Wayne Smith]

I've used this WW store for the past year or so. This is the first time I've added lead, but that was from a shower pan, I don't think they used zinc in them. The boolits appear fine, no oatmeal looking surface. Have loaded some, don't know how they will shoot, or if I can tell since it's a new barrel - TC Encore Katadin. Don't know when I'll get to the range with all the home projects, either.

[Wayne Smith]

And they weigh right at 343gr, so if there is zinc its not much. At least, I would expect a lighter boolit if there was zinc in the mix, not a heavier one.

[DLCTEX]

I got normal weight boolits with some zinc contamination, the biggest indicator was a silver look to boolits with a smooth shiny surface. I just noticed that the mold is a hollowpoint. If you aren't an experienced hollowpoint caster, the point pin must be kept HOT, or you will experience incomplete fillout. Some use a wire loop to suspend the pin in the melt while it is out of the mold, or some other heat source. DALE

[Wayne Smith]

Strangely enough, Dale, the improper fillout was always the base, the points were perfect. Yes, I know to keep the pin hot.