Extreme Dust Test

performance in severe dust conditions of various 5.56 mm carbine designs for use in future requirements generation. Specifically, determine the reliability of weapons within their service life that receive a minimal maintenance regimen in severe dust conditions.
Engineering test originally designed to detect minor differences in lubricant performance. Extreme nature of test (number of rounds and minimal maintenance in severe dust environment) is not representative of a weapon’s realistic experience in an operational environment.
Applicability: This test did not address…
Reliability in typical operational conditions
Reliability in harsh environments other than severe dust
Weapon parts service life (although some insights can be made)
Life cycle maintenance costs
Any other aspects of weapon effectiveness, suitability, or survivability other than reliability performance in severe dust conditions

round test fire
Fired in 120 round dusting cycles; wipe and re-lubricate every 600 rounds, full clean and re-lubricate every 1200 rounds
Lubrication with CLP IAW manufacturers’ specifications (light vs. heavy application, and which parts)

Dust Test Design

Sample size sufficient to draw statistically sound conclusions with a high degree of confidence.
Controls: dust application, temperature, lubricant application, cleaning

loaded
in Chamber

Dusting Process

120 rnds Firing

Weapons fully exposed
to Dust

Wipe down and Lube
Application
@ Every 600 rnds

Step #5

Step #6

Detail Weapons
Cleaning @ Every 1200 rnds

Repeat Steps #1-4 Five Times

Wipe and re-lube every 600 rounds; full cleaning and re-lube every 1200 rounds

Test Flow Chart

Repeat
Steps
#1-4
Five
Times

TEST

CYCLE

operational test
Laboratory environment
Extreme conditions
Systems pushed to technical limits
Control of variables
During extreme dust test each weapon:
Exposed to 25 hrs of dusting
Fired 6000 rds (equivalent of ~29 basic loads) and life of weapon
50 x 120 rd cycles
Wipe and lube every 600 rds
Full cleaning and lube every 1200 rds

Test addresses a single aspect of technical performance that could
inform development of future requirement that does not exist today

Stoppages per 60,000 rounds fired per weapon system

Only

Raw data from Fall 2007 Extreme Dust Test

etc.) and “wipe and lube” cleanings (after cycle 5, 15, etc.) seem to have positive impact on weapon reliability!

test.
This condition caused ruptured cartridge cases to occur on several weapons towards the end of test.

Number of Occurrences
M4: 1
XM8: 10
H&K416: 3
MK16 SCAR: 7

Safety Issue!

Condition requires the bolt to be replaced. Occurs at or before 6,000 rounds under extreme dust test conditions.

No significant difference in head space loss between weapon types!

extreme dust test
Each weapons type experienced ~1% or less stoppages of total rounds fired
Cleaning and heavy lubrication resulted in fewer stoppages for all weapons
All weapons exhibited significant wear that rendered them unsafe for firing beyond 6000 rounds without replacement of barrel and/or bolt.
Significant difference between EDT II and EDT III in results for M4
296 stoppages (EDT II) vs 863 stoppages (EDT III)
This indicates that test protocol may not be repeatable
Interaction of technical variables not fully understood at this point in time
Data continues to be analyzed
Are test results repeatable?
Can the data inform development of future requirement that is testable?
Does data suggest areas to improve design?
What is the state of the art and maximum possible technical performance envelope?

or replicate operational conditions
Soldiers clean and lubricate their weapons much more frequently than the test protocol
Soldiers normally carry
1 x basic load = 210 rounds in 7 aluminum magazines (~7 lbs)
2 x basic load = 420 rounds in 14 aluminum magazines (~14 lbs)
Soldiers expend less than one basic load in a typical engagement

Analysis; 917 assigned the M4 and used it in combat
Soldier confidence:
816, or 89%, reported overall satisfaction with the M4
734, or 80%, reported confidence that the M4 will fire without malfunction in combat
761, or 83%, reported confidence that the M4 will not suffer major breakage or failure that necessitates repair before further use.
Stoppages:
743, or 81%, of Soldiers assigned the M4 did not experience a stoppage while engaging the enemy.
74, or 19%, of Soldiers assigned the M4 did experience a stoppage while engaging the enemy.
143, or 16%, of Soldiers who experienced a stoppage reported a small impact to their ability to engage the enemy after performing immediate or remedial action to clear the stoppage.
31, or 3%, of Soldiers who experienced a stoppage reported an inability to engage the enemy during a significant portion or the entire firefight after performing immediate or remedial action to clear the stoppage.
12, or 1%, of Soldiers indicated the M4 should be replaced.

What we also know- 89% overall Soldier satisfaction of M4 Carbine

to TRADOC to inform the development of any future requirement
Determine repeatability of test results and study variables for understanding
Continue to support the Army with the M4 Carbine and use test results to improve the current force carbine where possible (the next ECP will be # 396)
Compete M4 design in 2009 or conduct a performance based competition if developed technical performance requirements differ significantly from existing requirements

Test addresses a single aspect of technical performance that could
inform development of a future requirement