I just started with the Lyman 500 gr mold today (the 45-70 Govt). Ran temp up to 750 on the little Lee bottom pour. Automatically threw the first 12 back in the pot to heat the mold. Then ran off 50 boolits. Had a total of 4 too light (more than 1 gr less than average, and one too heavy, 45 were all plus or minus .5 gr!!! The best consistency I've ever had. Kept the thermonitor in the pot so temp was not varying. Been pouring 38's for years. The only annoyance was the sprue plate loosening on a regular basis.