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| MIL-C-46946B(OS)
Radiographs of the entire production lot shall accompany the ballistic sample to the activity
conducting the production lot acceptance test. Discontinuities in serial numbers shall be
identified on the x-ray negative. Defective cartridges, found by the vendor, shall be clearly
identified on the negative and those defectives removed from the production lot. The serial
numbers shall be pen or ink stamped on the cartridge with approximately 1/8-inch-high characters.
The serial numbers shall be located apart from the other cartridge markings (see 6.2).
4.7.5 Airtightness. Each cartridge shall be subjected to specified pressure differential.
The method for determining airtightness shall be with a helium mass spectrometer. The helium leak
rate shall be converted to standard cubic centimeters of air. Failure to comply with the
requirements of 3.5.2 shall be cause for rejection of the cartridge.
4.7.6 Sealant application. Five cartridges from each production lot shall be selected for
this test. Failure of any cartridge to comply with the drawing requirements shall be cause for
rejection of the lot of cartridges.
4.7.7 Vibration test. Twelve of the 21 assembled cartridges of the first article sample,
x-rayed as directed in 4.7.4, properly identified, shall be subjected to vibration. The method
and procedures for performing the vibration test shall be in accordance with MIL-STD-810, Method
514.3, Test Procedure I, Test Condition I-3.2.5 (see 6.2). Then the 12 vibrated cartridges shall
be x-rayed again. Evidence of any disintegration of the primer, propellant, or igniter, or
derangement of any component shall be cause for rejection of the sample.
4.7.8 Functional. The following tests shall be performed by the Government.
4.7.8.1 Primer sensitivity. A quantity of cartridges, in accordance with table I, void of
igniter and propellant, from the first article sample and each subsequent lot shall be tested for
sensitivity. In the event loaded cartridges are selected for test, remove and discard all powder
charges from the test cartridge by sectioning the cartridge case around the periphery. Drop test
at 15 inches (adjusted) using a steel ball 1 and 1/2-inch diameter, weighing 7.94 0.02 ounces,
in a primer sensitivity machine with a cartridge holder approved by the acquiring agency. The
height of 15 inches shall be adjusted taking into consideration the actual weight of the ball so
that the energy level specified in 3.6.1 is achieved. Failure of the sample to comply with 3.6.1
shall be cause for rejection of the sample or the lot.
4.7.8.2 Ballistics.
4.7.8.2.1 First article. Twenty-one cartridges of the first article sample shall be grouped
and temperature conditioned as described in table II and 4.8. Following removal from the
conditioning chamber, the cartridge shall be tested as required by 3.6.2.2. Failure of any
cartridge to comply with 3.6.2.2 shall be cause for sample rejection.
4.7.8.2.2 Production lot acceptance. Twenty-one assembled cartridges from each production
lot shall be loaded into acceptable thrusters, divided into three equal groups, temperature
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