hi there wunderkind,
I was casting a bunch of bullets the other day using two identical moulds (Lyman 375 GC 270 gr) and one of the moulds just kept turning out trash bullets. I'd given both a rudementry clean in white spirit...
I'm wondering if any residule oil was left in the 'bad bullet' mould and whether this would have any bearing on the result. Both were hot.
Apart from a really good clean, any ideas?