Mould and lead not hot enough.
If you are ladle pouring - make sure thats hot too
My Lee 577 deep base minies and 457 ball are all useable from the first one.
I never smoke my moulds either - just scrupulously clean & make sure you flux the lead.
The only ones that go back in the pot are the ones I manage to dig out of the sand afterwards
Cheers
Roy
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