Years ago I bought a used Lyman 287448 mold at a gun show . . . it looked good but it turned out to be a lemon (probably why it was for sale). The mold halves did not line up properly, so it cast a very out-of-round bullet. There was a very noticeable step where the 2 halves of the bullet came together. Over the past few evenings I've been playing around trying to figure out if I could improve things. I checked the alignment pins/holes but they were fine. I tried driving the pins a bit farther out but that did not help anything. With the mold closed, the blocks (and the cavity) were visibly out of alignment.
Long story short . . . I removed the pins, carefully lined up the mold halves, clamped them in a machinist's vice and re-drilled the 5/32" factory holes up to #20 (.161"). I made new pins out of a couple of broken 6-32 and 8-32 taps (they both happened to have the same size shank). I chucked the pins in my lathe and using abrasive cloth, carefully worked them down. I made them as close to .162" as possible. They are not as snug as the factory pins, but I cast approx. 200 bullets yesterday and so far the pins have not moved. Before this surgery, the bullets were .0035" bigger at the seam. Now they measure .289"-.290" (Linotype alloy) all the way around. I'm really pleased with the results. I'm sure I'm not the first person to ever do this, but I thought some might find it interesting.
Long story short . . . I removed the pins, carefully lined up the mold halves, clamped them in a machinist's vice and re-drilled the 5/32" factory holes up to #20 (.161"). I made new pins out of a couple of broken 6-32 and 8-32 taps (they both happened to have the same size shank). I chucked the pins in my lathe and using abrasive cloth, carefully worked them down. I made them as close to .162" as possible. They are not as snug as the factory pins, but I cast approx. 200 bullets yesterday and so far the pins have not moved. Before this surgery, the bullets were .0035" bigger at the seam. Now they measure .289"-.290" (Linotype alloy) all the way around. I'm really pleased with the results. I'm sure I'm not the first person to ever do this, but I thought some might find it interesting.
