P.D. Measurement for MOD UN Thread

GaryD2023

Registered
Hello.
I have a question on how to properly measure the pitch diameter for a modified UN thread. The call-out is as follows:
13/16-12 UN-2A MOD
Major Dia: 0.763
Pitch Dia: 0.7567/.7512


As you can see, the pitch diameter is the same as a typical 13/16-12 UN thread, with only the thread's crest being modified to a smaller size.
Could I measure this thread's P.D. the same as I would a standard 13/16-12 thread using typical thread wires, or would I have to measure the midway point between the minor dia. and the truncated major and calculate it that way?
It seems like with the threads minor diameter, root width/radius, and pitch diameter being unmodified, it would still be correct to measure the thread using the typical thread wires.

Thanks in advance!
 
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