Original CW Cones or Old Repros?

[VMI88]

I recently found a stash of older black powder parts. Some are clearly reproduction but there were a few small parts I thought might stand a chance of being original.

These cones are threaded 5/16 x 24 and are apparently blued. It's hard to make out from the picture, but the internal geometry is different than I've seen on any reproduction. The opening in the nipple portion is a narrow inverted cone that leads to a short, straight channel, and then opens up into a larger cone in the threaded portion. All the modern reproductions I've seen have a solid bottom with a small flash hole rather than the bottom being completely open like this. This sounds like the description I've read of original cones but I couldn't find any pictures to compare.

[VMI88]

The next two cones are similar but have a much thicker wall on the threaded portion. Also, the interiors aren't cone-shaped but rather have a straight, narrow channel in the nipple portion and a wider straight channel in the threaded portion. There isn't a transition between the two: the narrow channel just opens directly into the wider channel. Any assistance in identifying these two types of cone would be much appreciated!

[Carolina Reb]

The second pair look closer to original. One way to tell for sure is that original cones use a 55 degree thread angle and the top and bottom of the thread is rounded, like Whitworth threads. Modern taps are 60 degrees with square ends. The modern threads will screw into original barrels, but if the barrel threads are in good shape, you will feel resistance as the cone screws down.