Rick, after casting with the mould I can guarantee those are shadows. Bullets fell out of the cavities like money from your pocket on tax day.
Sized and checked bullet along with a case with bullet to see how they would chamber. That is the max length for the cylinder. Look at that bearing surface.
Rick said a snug slip fit? This is a sized bullet inserted by hand held in place by friction with the cylinder held vertical. Can it get much better?
Mock up round chambered fully. Fills the throats pretty well. It is snug but the case easily ejects. You definitely feel when the bullet enters the throat.
Ignore the nose, I tried one a bit long and I had tap it farther into the case to get the cylinder to open.
Bullets weigh 284 with this alloy. The alloy is a mix I ended up with when I melted down 75 pounds of cast bullets I had sitting around. No idea what the exact composition is but I bet it is close to WW plus a little tin. Runs 14 BHn or so air cooled.
From the mould they run .433 but they size very easily to .430+
Awesome work Tom, couldn't have asked for better.