I don't know if it improved the cast because I rarely have an issue with a mold in that I cast with them so often. If I do, the primary cause tends to be the fluxing of my material. The one worry with the new design that I had was in applying the stick lube that I use on the pins. I thought that on a hot mold the lube might wick into the nearest cavities pronto this disabling two of the six cavities. With just a trace of stick lube on the blade of a slotted screwdriver, I touched the pins. I had a paper towel ready and followed up by placing a corner of the towel between the pin and cavity. Sure enough that wax flowed right along that channel toward the nearest cavity but the towel stopped it. I cast about 150 bullets and never had to apply lube to the pins again.
The sprue plate needs to be adjusted as with heat on the mold it applies too much pressure in the mid point of the mold thus bowing the mold halves. I just file the cutout where the sprue plate cams over to lock and that relieves the issue. I find this a common issue with the six cavity molds, Lee must feel that the sprue plate needs to lock and I disagree. If you want round bullets vs. out of round, you need to hold pressure on the handles just like the single and double cavity molds use! Those scratches on the upper side of the block (first image) is from too much pressure on the sprue plate when they closed it.
