MIL-C-18757/5A(OS)
4.6.6 Protective coating tests. Cartridge cases shall be prepared and tested in accordance with the
protective coating test of MIL-C-18757. The presence of white corrosion products will be permissible to
the extent that it does not interfere with chambering of the cartridge case. The black speck corrosion
rating procedure shall be as specified in OD 47471.
4.6.7 Chamber gage examination. Each cartridge case shall be chamber-gaged in receiver, Drawing
3030497, to determine conformance to the requirements of 3.7. A gage removal force of 35 pounds
maximum is permitted.
4.6.8 Ballistic test. The cartridge cases shall be loaded in accordance with Drawing 5366338. The
propellant charge shall be adjusted so that the ballistic test pressure at any temperature is as follows:
Service rounds 17.0 to 19.0 tsi-copper
Proof rounds 20.8 to 21.8 tsi-copper
Testing shall be performed in a Mk 75 gun mount and in quantities specified in table II.
TABLE II. Ballistic acceptance.
Type of lot
Number of round
Type of round
Round temperature EC
First article
70
Service
32
30
Proof
32
25
Service
49
25
Service
-7
401
Service
32
Production
101
Proof
32
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After firing, cases shall be rechambered in chamber gage.
4.6.8.1 Test procedure. All proof pressure rounds and five service rounds at each temperature, all
containing copper crusher gages, shall be fired in the single shot mode to determine compliance with the
pressure requirements. The remainder of the cartridges shall be fired in the automatic mode.
Temperature of the rounds shall be as specified in table II. Rounds shall be temperature conditioned for a
minimum of 24 hours.
4.7 Inspection of packaging. Packing and marking shall be visually examined for conformance to
section 5.
5. PACKAGING
5.1 Packing. Packing shall be in accordance with MIL-C-18757 with four cases packed in each box.
Each case is to be packaged in a bag in accordance with MIL-P-117, Type III, Class E, Style 1.
Approximate size of bag is 8.5 x 33 inches. Place a one unit bag of desiccant, per MIL-D-3464, Type I,
inside before sealing. Close bag and seal with tape conforming to PPP-T-70. PPP-T-60 may be used as
an alternate tape.
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