Ideal 357446 won't fill out with a mix that works fine in other molds

[Kim]

The mold I just bought drops its product like you dream about but the bullets don't fill out any place but the nose and base. The grease grooves are all rounded and you can see the corners aren't filled by looking at the bullet while it's still in either half of the mold. My mix casts great in other molds. I've varied temps to no avail. I sure could use some suggestions!

[BK7saum]

Bigger sprue/hotter sprue plate. I have had the same similar issue with a couple if molds.

Try a couple of pours letting alloy continue to run into/onto cavity and run off the sprue plate. It sounds like the sprue is cooling before the alloy is and it "sucks" the boolit away from the cavity walls when it is capped with a frozen sprue.

[Kim]

Thanks, I'll try that. It was also suggested to me that some of the air vents might be plugged. Can this really happen?

[Winger Ed.]

It was also suggested to me that some of the air vents might be plugged. Can this really happen?

Yes, and it's quite common.
If you can't feel the grooves with your fingernail, scrub them with some sort of solvent and a stiff tooth brush.

[45DUDE]

Someone may have sprayed the mold with a chemical when hot and it got in the pores. WD40 can do this. Get a hotplate and set on high and walk off for a few hours. have the lead hot and ready to pour. The boolits will be frosty at first but you have nothing to loose and will likely cure.