4.4 Test methods and procedures.
4.4.1 Hardness. -The method of test shall be in accordance with ASTM E18-67,
Rockwell Hardness and Rockwell Superficial Hardness of Metallic Materials.
184.108.40.206 Body. -Each sample body shall be sectioned , prepared and one hardness
impression taken within each of the areas as shown on Dwg. D7258807, a detail
220.127.116.11 Adapter. -One hardness impression shall be taken per test assembly
in the area prescribed on Dwg. D7258804. No cylindrical correction shall
18.104.22.168 Nose. -Three hardness impressions shall be taken, approximately 120°
apart, on the cylindrical diameter of each nose of the sample. The average
of the three readings shall apply as the nose hardness. Test sample noses
shall be supported on a mandrel approximately 0.5 inch in diameter. No
cylindrical correction shall be applied.
4.4.2 Adapter security. -The test for adapter security shall be conducted
using a standard tension testing machine of sufficient capacity. Rate of
pull shall be l½ inches ± 1/4 inch per minute.
4.4.3 Band tightness. - The method of test shall be in accordance with all
requirements of the operating instructions for the band tightness tester
(Dwg. B7259545, a detail of IEL 7258805). The inspection sample shall be
cycled through the tester to determine compliance with the rotating band
tightness requirement. The total measurement of radial void, registered
on the tester indicator at final ram pressure, shall be divided by four
(number of indenters) to determine the average radial void.
4.4.4 Soundness. -The method of inspection shall be in accordance with all
requirements of Operating Instructions Manual, Eddy Current Flaw Detector,
Dwg. D110752O3 (a detail of IEL 7258805) for Detecting Metal Discontinuity
in Projectile Bodies for 20mm Ammunition, except for those inspection re-
quirements which are reserved for Government application, as specified
22.214.171.124 Application of defect standards. -Master defect standards, refer-
enced in the Operating Instruction Manual, shall apply to resolve inspection
discrepancies occurring between the results of defect standards supplied for
contractor "soundness" inspection and those supplied for Government "sound-
ness" verification. (see 6.6)