The Tortured Path of the Army’s M855A1 AR-15 Round

This video was published on December 14, 2015, by The Wound Channel and shows the M855A1 round used as the U.S. Army’s primary battlefield cartridge being fired into clear ballistic gelatin. Impressive. For a round commissioned by the Army nearly six years ago, there’s still a lot about the load you may not know. Here are a few fun facts about the Army’s main battle cartridge, the M855A1 Enhanced Performance Round:

— In 2010, the United States Department of the Army began replacing the M855 with a new lead-free bullet, the M855A1 Enhanced Performance Round (EPR). We first mentioned the EPR in a blog post here. The rounds are frequently called “brown tips,” in contrast to the “green tips” of regular XM855. But the M855A1’s tip is actually bronze-colored — an anti-corrosive coating on its hardened steel penetrator.

— PJ Marx was the inventor of the projectile covered by a related patent (Patent No. 7,748,325, usually called the ’325 patent). Marx contacted individuals at the Department of Defense to share his design for a new, lead-free 5.56mm projectile after the Sept. 11 terrorist attacks. Marx first spoke with Army officials about the Enhanced Performance Incapacitative Composite (EPIC) round in 2004, and Marx filed a patent application on the EPIC round in 2005 and assigned the rights to Liberty Ammunition, a company he founded in 2005.

— After the government unveiled the M855A1 round, Liberty alleged in a lawsuit that through conversations with Mr. Marx, the Army was able to copy the design and give it to unauthorized recipients, including some who worked with vendors of ammunition to the Army.

A trial at the United States Court of Federal Claims was held in Washington, D.C., last year, commencing on June 23, 2014, and ending on July 8, 2014. The court found the government’s M855A1 ammunition design did infringe on Liberty’s patent. The presiding judge in the case, Charles F. Lettow, awarded $15,617,533.68 in damages to to Liberty Ammunition, which paid for the rounds the government had already made and supplied to soldiers. Also, Lettow awarded to Liberty a 1.4-cent-per-round royalty through October 20, 2027.

— The royalty should pay Liberty well. The Army and other military branches and agencies ordered more than 158 million of the M855A1 rounds in fiscal 2013, and Army budget documents from 2014 showed plans to purchase at least 65 million M855A1 rounds in fiscal 2015. Contractors for the rifle/machine gun ammunition include Orbital ATK’s Lake City Army Ammunition Plant in Independence, Missouri, and Olin Corporation’s facility in East Alton, Illinois.

— A primary reason for creating the M855A1, according to a June 2010 release from the Picatinny Arsenal in New Jersey, had nothing to do with performance in the field: “The M855A1 Enhanced Performance Round is the first environmentally-friendly bullet resulting from a larger ‘greening’ effort across the Army’s Small Caliber Ammunition programs. Other greening efforts include 5.56mm tracer, 7.62mm ball and green primers.”

The Army said, “The 5.56mm Ball, M855A1 Enhanced Performance Round (EPR) contains an environmentally friendly projectile that eliminates up to 2,000 tons of lead from the manufacturing process each year in direct support of Army commitment to environmental stewardship” — a fact many taxpayers may not have known was an issue in ammunition procurement.

— The EPR replaced the green-tipped 5.56x45mm NATO XM855 standard ball, the cartridge that raised such a ruckus last year because ATF was going to ban it for civilian use. No question, the M855 has its critics. The M855 incorporated a hardened steel penetrator; a lead slug; and a forward-drawn copper jacket, and had a weight of 62 grains when it became the standard NATO ammunition.

Post-combat reports and surveys in the 1990s said that some soldiers were reporting instances of through-and-through hits on enemy combatants who would return fire despite being struck by the standard ammunition. One such field report in fact said, “We had a[n] enemy that had been hit 14 times in the fatal zone and was still returning fire on us. . . . [A]fterwards when we checked his body, most of the shots went clean through him with minimal damage.”). These inconsistencies were a result of the M855 (and M80) being yaw-dependent, according to court documents in Liberty Ammunition’s lawsuit against the government.

“At a high angle of yaw, the projectile typically strikes a soft target without exiting the body. In doing so, the bullet transfers all of its energy within that target, which increases the severity of tissue damage and therefore, the likelihood of incapacitation. Conversely, at a low angle of yaw, the bullet may pass through a soft target. If it does not puncture a vital area, such as an organ, the through-and-through hit will only cause minimal damage because the projectile traverses the body without expending significant energy,” testimony from the case showed.

— Besides being “green,” the M855A1 is a better fighting round because it is less yaw-dependent. Also, the Army said in a release, “The M855A1 is tailored for use in the M-4 weapon system (Colt M4 Carbine and Colt M4A1 Carbine Short Barreled Rifle platforms) but also improves the performance of the M-16 assault rifle and M-249 (FN M249 Squad Automatic Weapon and Light Machine Gun) families of weapons. The M855A1 steel penetrator is effective against light armored targets while its three-piece construction maintains operational capabilities against unprotected personnel targets. The M855A1 enhances performance on hard targets or barriers, and contains an improved propellant that reduces flash.”

— However, the M855A1’s bullet has a copper core that is lighter than lead, so to add extra weight to get to its fighting weight of 62 grains, the bullet was made a little longer (about 1/8 inch), which requires it to be seated deeper in the casing, because the OAL of the cartridge still needs to mike out at 2.248 inches or it won’t fit in M4 magazines. Deeper seating in the casing can contribute to higher chamber pressures.

— Cheaper Than Dirt! does not list M855A1 for sale to the public. Liberty makes its National Defense 5.56x45mm Product Number T3(CS)-556×45 available only to military and law-enforcement buyers, according to the company’s website listing.

Liberty’s specifications for its National Defense 5.56x45mm round call it a “a copper/steel, 3-piece, armor-piercing, enhanced performance, lead-free round. Weight is 62 grains, and it produces 3,100 fps of muzzle velocity. Accuracy is claimed to be greater than 2 minutes of angle (MOA) @ 600 meters. Liberty says the ND 5.56mm will penetrate NATO steel, oblique glass, and level IIIA body armor, and an aluminum engine block, while fragmenting up to 9 pieces in soft tissue.

— If you get a chance to shoot some of the M855A1 through your agency, the new round is claimed to shoot flatter than the XM855. The M855A1 is listed as having a muzzle velocity of 3,100 fps compared to 3,025 for the M855. Accordingly, optics with displays made to coincide with the M855’s ballistics may be off. Also, the M855A1’s better penetration on steel may damage downrange target stands.

— The Office of the Project Manager for Maneuver Ammunition Systems at the Picatinny Arsenal produced a short list of items that “soldiers need to know when using this round:”

  • Dramatically improves hard target performance
  • Provides dependable, consistent effects against soft  targets and CQB performance (no more ―Thru and Thrus‖)
  • Significantly improves performance at extended ranges
  • Match like accuracy
  • No weight increase, flash reduced, increased velocity. 
  • [There’s] A noticeable gap below the penetrator ― spinning tips are normal, and do not impede performance in any way.”

Have you had a chance to shoot the M855A1? Do you think it lives up to its billing? Let us hear about your experiences with it in the field or at the range.

The Mission of Cheaper Than Dirt!'s blog, The Shooter's Log, is to provide information—not opinions—to our customers and the shooting community. We want you, our readers, to be able to make informed decisions. The information provided here does not represent the views of Cheaper Than Dirt!

Comments (29)

  1. In California we are forced to use lead free ammunition. The new lead free ammunition would be a significant boon to our shooters here on the Central Coast that have to participate in not causing lead poisoning in California Condors. It looks to me that a perfect lead free choice is being denied to hunters in favor of much more expensive copper rounds.

  2. For the author only:

    Where is your data on MV from? Did you chronograph it and with what device? What altitude? What temperature? What length barrel? What twist rate? What rifle?

  3. Ammo and rifles don’t win wars. Example: in Vietnam, to kill one enemy, it took on average over 50 thousand (!) rounds fired from small fire arms. Result: lost war. The WWII ended with two bombs dropped. Result: complete surrender. Wars are not won with small fire arms. All this is for feel good (or bad) for the troops and or/media.

  4. That video appears to be doctored…can’t quite put my finger on how though. That said, the military should have stayed with the 7.62NATO…much better than the 5.56 all around.

  5. There’s something funny going on with this video. There is an object pre-placed in the front face of the gel block which later explodes internally during the dynamic portion of the event. The brownish gasses venting from the front of the channel contain residue from this exploding object. Not sure what that item was but it really colors all the rest of this video in a bad way. I’m not sure what we’re watching here but I seriously doubt it’s a clean M855A1 shot into a gel block. The producers ought to be clear about explaining what went into this show.

    1. Glad Im not the only one who thinks somethings funny here. The response I got was “its hot expanding gases”. I dont buy that.

  6. I built a 25×45 sharps, and so far the best load I’ve come up with is a 90 bthp. I didn’t have to modify anything other than a barrel change. .257 rd in anything from 70 to 100 gr rds have much more punch down range compared to the heaviest.223 rd. Easy change for the military to increase power yet keep the same accuracy and trajectory as the .62 .223.

  7. To whom it may concern,
    The 55 grain bullet had the best damage to hit ratio on soft targets.
    And less weight per round. Wasn’t that the little bullet plan?
    The 1:8 twist works good for 62 grain bullets, and drives a 55 grain bullet crazy on impact.
    Now, if one needs AP rounds; carry as need.
    P.S. The US GOVT. sucks at war. So get out, or kill, and pillage properly. Where is my cut Uncle Sam??
    What’s next Red ascots?
    Thank you, Evelyn

  8. The M855 is a mediocre round and the M855A1 isn’t much better. Nothing in 5.56 can penetrate a concrete masonry unit with a single shot, something which can be done with the 7.62 x 39 or the 300 BLK. The 77 grain Mk 262 load has a much better ballistic coefficient and better soft tissue performance. The Mk 318 Mod 0 is a better short range load and has good expansion capability.

    Basically Uncle Sam has hyped this round while simultaneously wasting millions in taxpayer dollars. It’s the same philosophy that avoids excellent rounds like the 300 BLK and 6.5 Creedmoor. Our troops pay the price by going into harm’s way with underperforming ammo that has many of the same weaknesses as M855 while returning high chamber pressures and decreased barrel life.

  9. The detonation seen after the core separates and the temporary cavity contracts appears to be unburned propellant residue igniting. If the muzzle was close enough to the gel block and the barrel was short enough, it is very likely that a percentage of unburned propellant would travel behind the projectile and enter the wound channel before igniting. You can actually see some of the propellant inside the block prior to the detonation.

  10. I suspect they included the words “Armor Piercing” in the nomenclature for this new round, just to allow ATF to keep it out of civilian hands without any fuss like they saw recently when they tried to ban M855

    1. I wondered about that also. When the gel returned to its original shape, some dirty looking brown smoke was expelled from that explosion. The wound channel was marked out a little bit in some residue.

  11. What was the flash at the 36 second mark? It looked like an explosion as the wound channel collapsed on itself. It even caused smoke to form.

  12. It seemed to me to leave a piece behind about 5 inches into the gel block which later exploded producing gas and smoke exiting through the entrance of the wound channel. If this is correct I cannot see civilians ever getting this ammunition or the Geneva Convention ever sanctioning this particular round.

  13. I noted that with the new M4 round they actually decreased the “yaw” or did I read it wrong. The problem with the original round is that it only “yawed” once and therefor caused a wound that could be triaged. On the other hand the 5.45 x 39 mm Russian .223 round yaws twice producing a wound that cannot be triaged and is fatal in about 95 % of cases. People seem to forget that in a time of war, the intent is not to kill the enemy, but rather to maim him/her as to render the enemy incapable of shooting at us. It takes about three people to care for a wounded soldier and while doing so they cannot be shooting at our soldiers. ‘Enough said I was a foreign ammo specialist in the U.S. Army

    1. The idea is to INCAPACITATE the enemy. While the OFFICIAL idea may be to wound the enemy so that it takes people to carry him away/care for him, in the REAL world the grunts want the Motherf@cker DEAD so he is no longer a threat. This from a grunt from an earlier war. Dead people are harmless. So if he is still moving SHOOT HIM AGAIN until movement stops. Fragmenting ammo is better at this. The 855 was not good at “stopping”. VN era M193 was better as are a number of other rounds found in the combat zone today including the MK 262 mod 1 using a 77 gr BTHP match bullet.

    2. I served in Afghanistan, and I’ve seen firsthand how insufficient the 5.56 round is. Uh, in regards to your comment, I prefer my enemies to be dead.

  14. Really, no matter how you slice it, it’s still a pellet. They talk about being able to carry more ammo with the 5.56mm but if you have to shoot something more than once, then there’s no advantage. SOF has been trying to get a different rifle carrying bigger bullets for years.

    1. More to it than weight of ammo. Weight of the weapon is another issue. Controllability is another if used full auto.

    2. Couldn’t agree with you more. It is high time we discarded 5.56 and move to 7.62. But I’m afraid the cost of replacing every long gun in our military will prevent that.

    1. The Wound Channel provides some good info and if at the least its a data point useful for further interpolation.

      You shouldn’t openly knock someone else’s hard work unless you have evidence to your worthless comment.

      What have you done lately to contribute to the firearms community?

    2. I gave firearms to small children and the elderly for Christmas. Does that count? The Wound Channel guy is garbage.

  15. Nope, haven’t had the opportunity since I am not military or Law Enforcement. Hope to get some as civilian should be able to procure everything the military uses. But, with that said, I will stick to my 7 mm Mag hand loads. They may not be “armor piercing, but you can’t armor a head, and even if you could, 2000 ft/lbs of energy to a head/ neck will take anyone out. Mission accomplished! Glad our Goobermint cares so much about the environment! Sarcasm intended.

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