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|  MIL-A-12560H (MR)
w/INT. AMENDMENT 4
4.4 Sampling.
4.4.1 First article sampling.
4.4.1.1 Chemical composition. Samples for chemical analysis shall be taken from each plate
selected for the ballistic tests.
4.4.1.2 Impact samples. At least one impact test sample shall be taken from each submitted test
plate in accordance with 4.6.3.1 or 4.6.3.2 and each shall consist of enough material for four
impact specimens.
4.4.1.3 Ultrasonic examination. Each submitted test plate 3/8 inch in thickness and thicker, shall
be ultrasonically examined in accordance with 4.6.5.
4.4.1.4 Ballistic test plates. Three ballistic test plates for each nominal thickness range (see table
IX) shall be randomly selected and submitted for ballistic test. Any thickness within the range
can be chosen to represent any other thickness in the range but the three plates submitted shall be
of the same ordered thickness. Unless otherwise specified, the average thickness of each test
plate shall be determined at the test site by the test agency as indicated in 4.4.2.5.
4.4.2 Sampling for quality conformance inspection.
4.4.2.1 For chemical analysis. At least one sample for chemical analysis shall be taken from each
heat in accordance with the applicable method specified in ASTM A751 (see 6.6).
4.4.2.2 For hardness test. The Brinell hardness of each plate as heat treated in each lot up to 1 1/2
inches thick shall be measured in two places, one at each end of a diagonal on both plate
surfaces. The Brinell hardness of each plate as heat treated in each lot over 1 1/2 inches thick
shall be measured in four places, one at each end of a diagonal on both plate surfaces.
4.4.2.3 For Charpy V-notch impact tests. At least one sample shall be taken from a plate
representing each lot for Charpy V-notch impact tests. The sample shall be the same thickness as
the plate they represent and large enough to obtain at least two specimens, in each direction,
from each sample in accordance with 4.6.3.
4.4.2.4 Ultrasonic examination. All plates 1/2 inch and greater in thickness shall be examined
ultrasonically. The ultrasonic examination shall be performed in accordance with 4.6.5.
4.4.2.5 For ballistic acceptance samples. Unless otherwise specified in the contract or order, one
test plate shall be submitted from each lot. The minimum plate size shall be as shown in table IX
for the applicable thickness. Unless otherwise specified, the average thickness of each test plate
shall be determined at the test site by taking the average of four thickness measurements.
Measurements shall be made at least 1 inch from each edge but preferably at random in the
intended impact area. Thickness measurements for plates up to and including 2.750 inch shall be
read to the nearest 0.001 inch. Plates over 2.750 inch shall be read to the nearest 0.01 inch. If a
producer submits plates outside the specified plate tolerances (see tables III, IV and V), the
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