Howdy Boys
Well, like most things, I seem to do things a bit differently than most. I do use a spray on mold release. The first prototype J/P 45-200 molds were a bear to get the bullets to drop out of. Nothing worked for me, not smoking the molds, or anything else. I finally got ahold of a can of silicon mold release formulated for the injection plastics industry. It was the only way I could get those first J/P 45-200 bullets to drop easily out of the mold. Some minor changes were made in the design when it went to production, and they drop out of the molds much easier now.
I have since broken the valve stem on that can of special mold release, so I just use the regular mold release that Midway sells. I don't notice any problem with it building up and causing undersized bullets. The key is, like the old Brylcreem ads, a little dab will do ya. You don't have to slather it on with a spoon. I usually give my molds a quick, light spray, then I'm ready to go to town. Like any surface treatment, it eventually wears off and may need to be renewed during the casting session. Same with smoking the molds. A quick squirt gets me going again.
And I have to disagree with my good friend Howdy Doody. I find a lead thermometer to be very useful. Making a mark on the dial of a pot will only mark the temperature for the same amount of lead in the pot. When you add lead, the temp drops. Then it takes some time to come up to temp again. I like having a dial I can read. I like to cast a little bit hot, up around 800 degrees or more.
I cast my Mav-Dutchman 44 cal bullets from pure lead. I cast my PRS and J/P 45-200s from a mix of about 1/25 tin/lead. The reason for the different alloys is that is what my molds dictate to end up with the size of bullets I want. Lee molds are slightly less than perfect, and their cavity diameters can vary a few thousandths. I forget exactly how much right now, but the discussions I had with Lee over their tolerances told me that their mold cavities could vary by a few thousandths and still be in spec. My Mav-Dutchman mold is a little bit towards the high side of the tolerance. So I cast them with pure lead. Pure lead shrinks more when it cools then lead with tin added to it. That way, I wind up with bullets around .430 or so in diameter. My 45 molds on the other hand are a bit closer to the low end of the tolerance, so I throw in a little bit of tin to keep them from shrinking too much as they cool.
I've been using that same Lee Pro 4 production pot for a few years now. It works well with the Lee 6 cavity molds. You can empty a 10 pound pot in a real hurry with a 6 cavity mold. The other nice thing about that model is there is a little adjustable shelf under the pot. I have the height set just right so that I plop the mold down under the spigot, open it up, and slide the mold along the shelf so the lead flows into eacn cavity in turn. Kind of like a bartender lining up glasses and fillling them all up in one fell swoop.