ARMY AL&T FIGURE 1. COMPARISON CHART: M855 AND M855A1 EPR M855
Characteristic Cartridge Length
Bullet Weight and Length Tip ID Steel Penetrator Slug
Copper Jacket (FMJ) Lead Slug
Cup/Jacket Penetrator
Corrosion Resistance Propellant
Propellant Brass Case
Flash Suppressant De-Coppering Agent Velocity
Chamber Pressure Penetration
No. 41 Primer Soft Target Not Specified Lead
Copper Steel
None
WC-844 No No
3,113 ft/sec M855 Spec
3/8" Mild Steel @ 160m
M855 2.248 in
62gr Green
M855A1 EPR No Change
Core No Change
Bronze from Corrosion Protection
Copper No Change
Steel Arrow Head Yes
SMP-842 Yes Yes
Increased Increased
3/8" Mild Steel @ 350m
Improved Consistency and Range
Same Primer but with 4-Prong Stake
Same Jacket Material but Reverse Drawn
Copper Slug Steel Penetrator
Penetrator Jacket
M855A1
Different Propellant Same Case
In 1960, when Army Research and Development Newsmagazine—the forerunner of Army AL&T Magazine— first appeared in print, a major contro- versy was raging over the relative merits of the then-standard 7.62mm round and a lighter, higher-velocity 5.56mm alternative. The Army adopted the 5.56mm M16 rifle in 1967; it fired the M193, the first 5.56mm round. Nevertheless, the controversy continued over which caliber was better—5.56mm vs. 7.62 mm—as the magazine noted through the years. In 1982, a review by Army Research, Development, and Acquisition Magazine (as it was then called) of small-arms ammunition development praised the lighter weight and lesser recoil achieved with the
smaller round, yet observed that, “One of the inferiorities is, however, its pen- etration capability.”
In 1982, the Army adopted the 5.56mm M855 round to replace the M193 in an effort to achieve better performance at longer ranges with the M249 Squad Automatic Weapon (SAW). A steel penetrator in the front end of the M855 provides increased hard-target performance.
Development of the M16A2 rifle, which matched the twist of the M249 SAW, also allowed use of the heavier M855 round. The M193 is still produced today, largely for foreign military sales.
From 2003 to 2006, the Army con- ducted a study of available bullets, commercial and military, and found none that provided improved perfor- mance over the M855 against the target sets required of a general-purpose round.
Ensuring Consistency and Environmental Responsibility
In post-combat surveys and field reports from Iraq and Afghanistan, most Soldiers have indicated that the round works fine, delivering the desired effects against threat targets. But some Soldiers have reported that the round did not perform consistently, causing concern in the ammunition community.
Once the M855A1 replaces the leaded M855, it will reduce the amount of lead in production by approximately 2,000 metric tons yearly, based on the amount now used to make the M855.
33 OCTOBER –DECEMBER 2010
In parallel, mounting environmental concerns drove the Army to consider replacing environmentally unfriendly materials such as lead. The Army’s ammunition community, led by PEO Ammo, saw an opportunity to address the two concerns associated with the M855 round—lead and consistency.
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