Why am I getting what looks like multiple parting lines?

[Quigley_up_Over]

I have been seeing a common theme in my cast boolits: what appears to be "multiple parting lines". The ONLY thing I can figure is that when I open the mold, the boolit is somehow rubbing on the sharp inside edge of the mold split line as it falls out? Strange problem. It's VERY annoying!

[dubber123]

Probably the mold cavity is drilled slightly off center. I'm guessing you have to tap the mold a few times to get it to release? If so, you are correct, it is the edge of the cavity leaving the marks on the still soft boolit. I've had good luck GENTLY, (especially on aluminum molds), using a fairly soft Bronze bristle brush to lightly break the edges on the cavities. Good luck.

[williamwaco]

This is quite common and unless it is very deep, it will disappear in sizing.

When you are opening the mold you are opening it slightly, the bullet is beginning to move and then you are closing it partially and the edge of the empty side of the cavity is marking the bullet just a little off the original parting line. Alternatively, the bullet is falling out of the cavity and falling into the opposing empty cavity on the other side of the mold. I have personal experience both of these occurrences. My grandmother always told me "Haste makes waste" be careful when you open the mold and eject the bullets.

Try this:
Cut the sprue. Be sure you are holding the mold tightly closed during this procedure.
Next, forget about dropping the bullet and concentrate on opening the mold completely. Hold the mold so that the cavities are vertical during this procedure. If the bullets don't "fall out" turn the mold at an angle to the vertical but not far enough that when the bullet falls out, it can fall against the empty cavity on the opposing block.

Where is Up-Over?


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[stubshaft]

It looks worse than it really is and will usually be wiped off when sizing.

[Quigley_up_Over]

OK I figured it out, thanks to your help. What I was doing before was opening the mold post-pour, THEN tapping out with a rawhide hammer. Now what I do is tap with the hammer BEFORE opening the mold, and the boolits fall right out, sometimes just a little wiggle is needed but generally they fall right out, in PERFECT form! Good stuff. Thanks guys.