The following document was requested in June of 1999, and took approximately 8 years to obtain.
It was listed in a DTIC bibliography, with no report title, and no information. So, intrigued, I requested the report number, and this is what came up.
What is interesting, is that the document, now more than 45 years old, is still heavily classified.
Weapons Classification Guide [63 Pages, 3.64mb]