David
After viewing the photos of the finished taper end it looked familiar, so I measured the same ends of the vintage nuts that I am now using.
The end has been machined off flat & remains .040 wide after the inside (thread) has been chamfered @ (looks like 90deg.) to a face width of approx .060. All edges are nicely finished.
So it would appear whoever made these up took the design under serious consideration as have you.
The only shortcoming is the internal hex, which can present a problem on installation & removal if one is not very carefull.
Craig