Some things you might want on hand
If you are casting with a 6-cavity Lee 158gr mold, you need a 20-pound capacity furnace. Otherwise, you'll be sucking it dry and have to wait until it melts a new batch. Operate the furnace outdoors on maximum heat, keep it nearly full, have small ingots preheating on top or on a hotplate nearby, and feed them to keep the liquid level up.
With a Lee 20-pound furnace to cast from, and a 10-pounder acting as a melter, using 6-cavity Lee molds I can cast 24 bullets per minute for long stretches of time.
May I suggest you either use hot soapy water and an old toothbrush to clean your cavities before casting, or Brake Cleaner. Also, get graphite mold spray or wood matches to smoke the cavities: the cavities may cast better with it.
There is an adhesive wear mechanism that is common with hot aluminum called galling. There is a sprue plate lube available on the Cast Boolits board called Bullplate Sprue Plate lube which eliminates it. Scribbling all over the top of the blocks and the bottom of the sprue plate with a Carpenter's Pencil will also work, but not as well. The mold hinge needs either Bullplate or bullet lubricant as a lube.
I like to drop bullets from the mold into a 5-gallon bucket of water. With this technique, they don't ding each other the way they do with the traditional box with an old towel in it. If you use a Lead alloy that has both Tin and Antimony in it, water dropping will also give you remarkable hardness.
Don't eat or smoke while casting, as most Lead poisoning comes from ingesting it through the mouth. Do not stand over the furnace, as if you get the Lead really hot it will off-gas: I operate the furnace with the temperature control set high, but the Lead never gets that hot as I am continually feeding it more small ingots.