MIL-B-70511B(AR)
AMENDMENT 2
*
4.5.4: Delete in its entirety and substitute the following:
"4.5.4 Endurance. A minimum of two rifles shall be used
for this test. At least one half of the test rifles shall be
M16A2 rifles and the remainder of the rifles shall be M16A1
rifles. Testing shall be performed from a Government approved
test fixture. A total of 10,000 rounds shall be fired on each
M2 Bolt. Testing shall be conducted in cycles consisting of
firing four 30-round magazines for a total of 120 rounds.
Start the endurance test with a M2 bolt in a M16A2 rifle.
After each firing cycle, the M2 bolt shall be sequentially
rotated through the total number of test rifles, alternating
between M16A2 and M16A1 rifles. Firing sequence for both the
M16A1 and M16A2 rifles for a test cycle is as follows:
3rd Magazine
4th Magazine
2nd Magazine
Rifle 1st Magazine
Auto
Semi
Auto
M16A1
Semi
Semi
Burst
Burst
Semi
M16A2
After each cycle, the barrel shall be cooled to the point that
it is capable of being held by the bare hand. Supplemental
cooling is permissible. Lubricant conforming to MIl-L-63460
shall be used. After every five cycles, the M2 Bolt shall be
lubricated, and cleaned and lubricated after every 10 cycles.
At the completion of 4,800 rounds fired and again at the end of
the 10,000 round endurance test, each bolt carrier (P/N
11833494) and each bolt (P/N 11833495) shall be inspected using
magnetic particle inspection. Any cracked or broken bolt
carrier or bolt shall result in failure of the endurance test.
If there are any other broken, cracked or unserviceable parts,
they shall be replaced. Both the M16A1 and M16A2 rifles shall
be cleaned and lubricated as stated in paragraph 4.5.4.1.
Cyclic rate of fire measurements shall be performed during the
first testing cycle, and during the first testing cycle using
an M16A2 rifle after the M2 bolt has been lubricated, as stated
above. Cyclic rate of fire measurements shall be performed on
the second magazine of a cycle using a M16A2 rifle. The cyclic
rate of fire shall be measured in accordance with 4.5.3. All
malfunctions shall be recorded. If more than the number of
malfunctions specified in 3.4.4 occur, that are attributable to
an individual M2 bolt, the sample shall have failed the
endurance test.
*
4.5.4.1: Delete "Rifles shall be lubricated as specified below at
the beginning of the test and after the third cycle in every 5
cycle increment. Rifles shall be cleaned and lubricated at the
end of every 5 cycles." and substitute "Each rifle shall be
lubricated as specified below at the beginning of the test and
at the end of each 5 cycle increment fired on that rifle. Each
3
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business