MIL-D-60873A
3.4 Components.
3.4.1 Primary components. For the purpose of this specification, the M42 Primer, Delay Charge and the
output material charge are considered primary components. Only primary components from a single lot shall
be used in a production lot of cartridges; however, one primary component production lot may be used in more
than one cartridge production lot (see 6.7).
3.4.1.1 Primer. The primer shall conform to the applicable drawing and reference specification. Only
percussion primers from lots manufactured within the last 24 months or recertified within the last 12 months
shall be used in these units. Prior to assembly into a delay element, the primer shall be visually examined in
accordance with 4.6.5 and radiographically examined for defects as specified in 4.7.1.
3.4.2 Protective finish. The finish of each component part shall be in accordance with MIL-A-8625 and
the applicable drawing (see 4.7.2).
3.5 Assembly.
3.5.1 Radiographic examination. Each delay element assembly shall be radiographically examined for
defects (see 4.7.3).
3.5.2 Vibration. The assembled delay element shall withstand vibration as prescribed in MIL-STD-810,
Method 514.3, Test Procedure I, Test Condition I-3.2.5 without evidence of any disintegration of the primer,
propellant, or igniter, or derangement of any component (see 4.7.4 and 6.2).
3.6 Functional requirements.
3.6.1 Delay element performance.
3.6.1.1 Misfires. The ignition delay element shall not fail to fire.
3.6.1.2 Ballistics. The ignition delay charge shall consist of barium chromate, as specified in MIL-B-550,
and boron, as specified in MIL-B-51092, in the proportion and quantity fixed by the contractor to produce the
ignition delay times required in table I (see 6.5.1).
TABLE I. Ballistic requirements.
Ignition delay time (sec)
Lower
Upper
Temperature (· F)
-60 to -70
1.200
1.600
65 to 75
1.300
1.500
195 to 205
1.100
1.500
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