There was a thread here about 2 months ago about using Kroil in the mould cavities to improve the "castability" of a mould. Here is a link to the original thread.
http://castboolits.gunloads.com/showthread.php?t=55260
I will admit I had my doubts about it. Commonly accepted cast boolit wisdom is that any oil in a mould is bad and will cause wrinkled boolits. I do know from experience the preservative oil in a new mould needs to be removed or you get wrinkles. So from that many casters infer that all oil is bad and to apply oil on purpose just makes no sense at all.
I have a new Lyman 311359 that I acquired to feed a National Postal Meter 30 Carbine. The boolit does well in the carbine, but the mould is a real chore to use. The front cavity hangs up badly, and requires many forceful blows to release. I cleaned and cleaned and looked for burrs, but still the production rate was low and the fatigue and frustration level high.
So today I used Kroil in the cavities. The Kroil I have is liquid, not spray, so I soaked a Q-tip and throughly wet both cavities, waited a bit, then swabbed the excess out. Once the mould got up to temperature, it was like a different mould. The front cavity still needed an occasional tap, but the improvement was astonishing. My production rate shot up, and the frustration was way down. I quickly got into that "groove" where boolits are falling perfect with every cast and you want no interruptions. It was a beautiful thing.
So if you have a balky mould, ignore past "wisdom" and try Kroil in the cavities.