w/INT. AMENDMENT 4
3.2.8 Identification marking. Identification marking and records shall be such as to ensure
positive identification of all plates, including test samples and specimens, with the lot and
corresponding heat from which they were produced. First article and acceptance ballistic test
plates shall also be marked with the manufacture's name or trademark, the number of this
specification, and the ordered plate thickness in inches. First article plates shall be marked
"PRE," acceptance plates "ACC," and retest plates shall be marked "R1" and "R2." If a second
set of retest plates are submitted they shall be marked "RR1" and "RR2." The marking shall be
approximately 1/16 inch deep and approximately 1/2 inch high and located along the edge with
the lifting hole, if present, and shall be stamped into the surface unless the plate hardness makes
painting necessary. All plate markings shall be highlighted with a highly visible yellow or orange
border such as fluorescent paint or highlighted with a special white paint intended to delineate
and highlight stamping. The primary plate rolling direction shall be identified. Manufacturers
supplying armor, to be used for proving ground testing of ammunition, are required to:
a. Mark each class 3 plate with one foot square blocks showing thickness at the center
of each block. The acceptance of each plate shall be based on these measurements
meeting the thickness requirements set forth in table V.
b. Stamp each plate "HOMO, class 3, MIL-A-12560, plate No. ____, heat No.____."
Stamping shall be approximately 1/2 inch high letters to a depth approximately
1/16 inch. Location of stamping for all plates shall be in the upper right hand corner.
3.2.9 Information required. A statement showing the product analysis of each melt and complete
details of the heat treatment of each lot shall be furnished for the files of the procuring activity.
All elements of the chemical composition shall be shown in the statement, including special
additives or hardening agents, whether shown in table I or not.
TABLE V. Thickness tolerances for class 3 armor plate. 1/
Specified plate thickness,
plus or minus,
To and including
1/ This armor is not intended for use in combat vehicles. To obtain these thickness tolerances
special surfacing finishing shall be required.