I post infrequently, being unable to assess my qualifications you should thus take my response for what very little it's worth.
Please excuse the slow server- I'm not an urban resident, my connection to the 'net, while the best available to me, is not up to what city folks have become used to.
View down the barrel of the crimper:
The lead angle of the three "teeth" is about 70°, the trailing angle is about 30°. The lead angle is clearly visible at ~ 2:00, the trailing angle at about ~10:00. The flat seperating the two angles forming the teeth is about 0.04" on the outside.
A second view down the barrel:
The "cup" in which the "teeth" are located is a few thousandths larger than the diameter of the hull to be crimped, it's about 0.25" deep with the "teeth" standing up from the bottom of the "cup" by about 0.12".
A view from the side:
Note that the center "plug" is about the same height as the "teeth".
The crimper "closed" having just completed a cartridge:
The handle that revolves the crimping head is turned clockwise (when viewed from the handles end of the machine).
A completed cartridge and the crimper shown "open":
The cartridge labeled 3-1-5. Three drams of black powder, 1 oz of #5 shot...
BTW, I'd recommend looking for a used roll crimper before I built one- I had little trouble finding any of mine except for the one in 28 gauge.
Price was modest, I gave $10 to 30 each.
Bob