I agree with the lubing with something other than bullet lube. I use Mobil 1. I have a case of it on hand for my truck. (92 Mazda with 345,000 Problem Free miles, though it is near time to do a break job.) I use a pipe cleaner, I preheat the mold on a gas stove. I dip the pipe cleaner, and then squeeze off the excess. I lube under the sprue plate, and I Lube the pins, and pivot point. It smoke for a couple of minutes, and is then good for the duration of my casting session.
Ok now back to casting. Need more .358 158 grain SWC for the weekend. It is casting weather. 75 and sunny with a wind chill of awsome.