So I when I got my speedloaders in the last century the loaders came with a 6 round post. They worked fine, but always bothered me. Updated posts were about $10 and with over 4 speedloaders....
Enter 3d printer, Blender software and calipers. 7 round post, reverse engineered with a nylock nut for security.
Here is the first set with an old pist for comparison.

Click image for larger version. 

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