4.7.6 Noise level. Test in accordance with Appendix D.
During the test an additional microphone shall be placed at the
right-handed gunners head position and the noise level recorded.
If the noise level recorded exceeds 135 decibels the test shall be
repeated with the microphone at the left-handed gunners position.
4.7.7 Screen perforation without BFA. The test shall be
conducted in the same way as screen perforation with BFA (see
function and casualty test procedure, Appendix C) except that
weapons be fired single-shot.
4.7.8 Attitude. The weapons shall be fired from a mount
which allows the elevation to vary from -85 to +85 degrees. The
test shall be conducted with one weapon of each type. All fired
cases shall be inspected and all weapon stoppages noted. The
quantity shall be fired in accordance with Table V. Rounds fired
in the M249 shall be linked.
4.7.9 Belt pull. Firing shall be in bursts of
approximately 10 rounds each, conducted from the M249 machine gun
with the gas regulator set in the adverse condition (max. gas)
position (if the weapon has a selector). A free hanging 200 round
belt shall be pulled by each weapon. Any stoppages shall be
4.7.10 Hot chamber effects. Immediately after the
continuous firing of the rounds in bursts from the specified
weapons (200 rounds in the M249 and 150 rounds in the M16A1 and
M231) a test cartridge shall be chambered but not fired. The
maximum time allowed for the firing of the rounds shall not exceed
two minutes. Thirty minutes must pass before any attempt to
remove the cartridge is made because of the potential for cookoff.
A cookoff during extraction of the cartridge can be hazardous.
After 30 minutes, the round shall be fired, if possible, and the
case extracted and examined. If the initial rounds cannot be
fired in the allotted time, the weapon shall be cooled and the
4.7.11 Sand and dust.
The general procedures outlined in TOP-3-2-045, (Type A
fixture) shall be followed.