“You do understand that .308 is only a Diameter.”
No! .308 is just a NUMBER. And most commonly refers to the .308 Winchester.
If you are specifying diameter you should say:
.308” DIAMETER bullet.
The discussion was of the Medical Examiner’s identification of the caliber of the bullets as small, medium and large.
In that context .308 would be caliber(bullet diameter) not which cartridge the bullet was fired from.
How would the ME know that anyway.