Threading and die question

[Sailormilan2]

I am getting ready to convert a round ball bolt knob to a screw on tactical style knob. The tactical knob takes a 5/16 x 24 threaded male end.
What diameter do I need so that the 5/16 x 24 die will work and thread the handle?

[mofugly13]

5/16"

The nice thing about external threads is that the major diameter is called out in the thread designation.

[Sailormilan2]

Cool. Thanks.