MIL-PRF-63460E specification. Test Criteria
Test weapons: The test weapon shall be the machine gun, 5.56 MM: M249. New weapons (guns that have been fired less than 5000 rounds) or guns with a used receiver with an all new operating group shall be used.
Firing residue removal: CLP shall provide cleaning capability to remove a minimum average of 80 % of the residue generated from the ignition of WC 844 propellant.
Weapon performance: CLP shall provide cleaning, lubricating and preservative characteristics to support operating requirements of the machine gun: 5.56MM, M249, when exposed to the following conditions
Weapons Firing Salt-Spray Test
Operating Requirements - Salt Spray: Salt-spray environments. CLP applied to an M249 that is then exposed to a salt-spray environment for 96 hours shall prevent any Class II or III stoppages, shall allow not more than two Class I stoppages in 200 rounds, and shall sustain a rate of fire of at least 650 rpm.
Salt-spray environment test: Only one machine gun shall be used for salt-spray testing and its’ performance alone shall determine if the requirement is met.
Inspection and preparation: The test weapons shall be disassembled, cleaned and lubricated with a normal application (see TABLE VI, Note 2) of the candidate product. With the bolt closed and the safety set in the "safe" position, the machine gun shall be placed in a salt spray cabinet and exposed to 5 % salt-spray in accordance with the Salt Fog Test Procedure of TOP 3-2-045, except that salt-spray and dry cycles shall be 48 hours each instead of 24 hours.
Weapons Firing: After the last salt-fog/dry cycle is complete, the weapon shall be moved to the firing position and loaded with an un-conditioned 100-round belt of ammunition. An initial burst of approximately 10 rounds shall be fired to validate the firing rate. The remainder of the 100-round belt shall be fired in 5-7 round bursts to check for stoppages. The second un-conditioned 100-round belt of ammunition shall be fired in the same manner, without further conditioning of the weapon.
Salt-spray environment failure criteria: Any Class II or III stoppage, more than two Class I stoppages in 200 rounds, or a reduction in the rate of fire below 650 rpm, shall be cause for rejection of the lubricant.
Weapons Firing Dust Test:
Operating Requirements - Dust Test: Dust environments. CLP applied to an M249 that is then exposed to very fine blowing dust for 50 minutes shall prevent any Class II or III stoppages, shall allow not more than five Class I stoppages in 500 rounds, and shall sustain a rate of fire of at least 650 rpm.
Dust Test: Three M249s shall be used for each candidate lubricant for dust testing and the average performance of the two weapons with the least number of stoppages shall be used to determine if the requirement is met. This test shall be conducted in accordance with provisions for static test procedure for dust exposure of TOP 3-2-045, except as noted.
Inspection and preparation: The test weapons shall be disassembled, cleaned and lubricated with a generous application (see TABLE VI, Note 4) of the candidate product. The weapons (with bolts and ejector ports closed, and barrel dust caps installed, or muzzles taped) shall be exposed to blowing dust. Dusting shall be as specified in TOP 3-2-045, except that the dusting cycle time shall be 10 minutes.
Weapons Firing: After the dusting cycle, the weapon shall be moved to the firing position, loaded with an un-conditioned 100-round belt and fired. An initial burst of approximately 10 rounds shall be fired to validate the firing rate. The remainder of the 100-round belt shall be fired in 5 to 7-round bursts to check for stoppages. This conditioning and firing sequence shall be repeated four times for a total of 500 rounds fired from each weapon.
Dust test failure criteria: Any Class II or III stoppage, more than five Class I stoppages in 500 rounds, or a reduction in the rate of fire below 650 rpm, shall be cause for rejection of the lubricant. Weapons Firing Cold Temperature Tests:
Operating Requirements - Cold temperature: CLP applied to an M249 that is then exposed to severe cold for 18 hours shall prevent any Class II or III stoppages, shall allow not more than two Class I stoppages in 200 rounds, and shall sustain a rate of fire of at least 650 rounds per minute (rpm).
Cold Temperature Test: Three M249s shall be used for each candidate lubricant for cold temperature testing and the average performance of the three shall be used to determine if the requirement is met.
Inspection and preparation: The test weapons shall be disassembled, cleaned and lubricated with a light application (see TABLE VI, Note 3) of the candidate lubricant. With the bolt closed and the safety set in the "safe" position, the machine gun shall be conditioned at -51 ± 2 °C (-60 ± 4 °F) for 16 ± 1 hours.
Weapons Firing: Weapons firing shall be conducted within the cold temperature chamber immediately after the conditioning cycle is complete. The weapon shall be loaded with an un-conditioned (ambient temperature) 100-round belt of ammunition, and an initial burst of approximately 10-rounds shall be fired to validate the firing rate. The remainder of the belt shall be fired in 5 to 7-round bursts to check for stoppages. Repeat the cycle, except condition the weapon for only 2 hours ± 15 minutes at the same temperature. Fire the second, un-conditioned 100-round belt in the same manner employed in the first cold temperature firing cycle.
Cold temperature failure criteria: Any Class II or III weapon stoppage, more than two Class I stoppages in 200 rounds, or a reduction in the rate of fire below 650 rpm, shall be cause for rejection of the lubricant.
Ammunition used during testing: Belts of ammunition shall be loaded as "combat mix", (4 ball (M855) and 1 tracer (M856)). The ammunition required for each of the three tests shall remain outside the individual environmental chambers, and shall not be conditioned. Definitions of stoppages:
Class I weapon stoppage: A failure that is immediately clearable (within 10 seconds or less) by the operator following prescribed immediate action procedures.
Class II weapon stoppage: A failure that is clearable by the operator (requiring more than 10 seconds but not more than 10 minutes) using only the equipment and tools issued with the weapon.
Class III weapon stoppage: A failure of a severe nature. The failure; (1) is operator correctable but requires more than 10 minutes, (2) operator cannot correct and requires assistance( no time limit), (3) requires higher level of maintenance, or authorized operator correction cannot be accomplished because of unavailability of necessary tools, equipment or parts.
TABLE VI. Weapons firing test summary.
Firing test Application Test Condition Rounds Failure criteria (Note 1)
Inspection Normal (note 2) Ambient temp 200 <700-850 rds/min
Cold temp (2 Cycles) Light (note 3) -51 ± 2 °C (-60 ± 4 °F) 200 <650 rds/min, or >2 Class I stops/200 rds
Dust (5 Cycles) Generous (note 4) After dusting Ambient temp 500 <650 rds/min, or >5 Class I stops/500 rds
Salt-spray Normal After exposure Ambient temp 200 <650 rds/min, or >2 Class I stops/200 rds
Note 1: Any Class II or III weapon stoppage during any test is cause for failure of the test.
Note 2: Normal application - as described in the operator's manual TM 9-1005-201-10.
Note 3: Light application - apply a thin film of lube barely visible to the eye.
Note 4: Generous application - apply lube heavy enough so that it can be spread with a finger.
