Barrel chamber. Insert the cleaning rod section and
chamber brush that has been dipped in cleaning solvent
into the chamber and use reciprocating plunge strokes and
rotational, 360 motions. Dry chamber with cleaning
Barrel extension. Using a small bristle brush that has
been dipped in cleaning solvent, clean the locking lugs
in the barrel extension. Remove-excess cleaning solvent.
Bolt carrier group.
With the exception of the Bolt
Carrier Key, Bolt Rings, Extractor Spring, and the
Ejector, disassemble all parts, wash these parts in
cleaning solvent and remove all carbon deposits.
Particular attention should be given to the areas under
the face of the extractor and behind the three rings on
the bolt. Clean the gas key hole with a worn bore brush
that has been dipped in cleaning solvent by rotating the
brush clockwise (repeat several times until clean).
Remove excess solvent from lower receiver cavity and dry.
Upper receiver. Clean with cleaning solvent and remove
all powder fouling. Clean the protruding gas tube using a
bore brush attached to a section of the cleaning rod.
Saturate the brush with cleaning solvent. (Do no use any
type of abrasive material to clean the gas tube. Remove
excess cleaning solvent).
Lower receiver. Remove all carbon residue from lower
receiver group assembly using cleaning solvent. Drain
excess solvent from lower receiver cavity and dry,
188.8.131.52 Magazines. Ten new 30-round magazines used in each
weapon shall be numbered and used during this. test. Magazines shall
be fully loaded for each use.
The following measurements shall be made
during this test.
a. Headspace. Headspace for weapons being fired with 30
round magazines shall be measured and recorded at the
beginning of the test and at the completion of the 17th
cycle. After the 17th cycle, the headspace shall not be
more than .0028 inch greater than the initial measurement
and shall not exceed .0024 inch over maximum.