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|  MIL-P-70679 (AR)
c. The body shall be fixtured so that no rocking, shifting or
deflection of the body will occur during the test.
d. The hardness tester shall not produce indentations deeper
than 25% of the indentor ball diameter or wall thickness of the
projectile in that zone.
e. Hardness readings shall be taken at least ten indentor ball
diameters apart. At least two readings shall be taken per
projectile and averaged in the zone where the obturating band groove
will later be machined.
4.4.5.1.2 Tension testing. From each sample selected for
testing in accordance with 4.4.3.1.2, two tension test specimens
(one bourrelet area, one boat tail area) conforming to the largest
obtainable standard or subsize flat or round specimen as prescribed
by ASTM Method E-8 shall be taken longitudinally from opposite sides
of the body, 180 degrees apart. The number of specimens and their
location is to determine the acceptability of the mechanical
properties requirements, and with the approval of the procuring
agency. The Government shall not be restricted from testing
additional specimens to determine the mechanical properties meet the
drawing requirements. Procedures and criteria for determining yield
strength, elongation, reduction in area and tensile strength shall
be as prescribed by ASTM Method E-8, except that elongation shall be
measured to the nearest thousandth (0.000) prior to conversion into
percent elongation. Percent elongation shall be recorded to the
nearest tenth (0.0).
4.4.5.2 Metal defects inspection.
4.4.5.2.1 Before paint (Magnetic particle inspection). (See
4.4.3.2) Projectiles shall be tested using procedures for the wet
fluorescent method as specified in MIL-STD-1949. Each projectile
shall be tested twice. Both transverse and longitudinal fields
shall be induced in the projectile using any method to establish the
fields. Between the two (2) tests and following the second test,
each projectile shall be demagnetized. The magnetic solid content
of the suspension shall be maintained at 0.2 - 0.4 mililters (ml) of
solids per 100 mls of suspension when oil is used and 0.15 - 0.35
roils of solids per 100 mls suspension when water is used. The
suspension shall be checked at the start of each day's production
and at intervals of not over four hours of continuous operation,
utilizing the procedures and equipment prescribed by section 4 of
MIL-STD-1949. When performing the test for solid content of the
suspension, if it is determined that it does not comply, all bodies
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