The Marine Corps is considering a change in service rifle from the M-16A2 to either the M-16A4 Rifle or the M-4 Carbine. Unfortunately, all three weapons suffer from a common shortcoming: the impotent 5.56-mm NATO cartridge. Merely changing weapons will not correct its deficiency in lethality.
The 5.56-mm round was spawned by the proposition that volume fire is as effective as aimed fire. Therefore, warriors with lighter-weight cartridges (in terms of physical weight as opposed to impact) could carry more bullets in their same basic load, put out a higher volume of fire, kill more enemy soldiers, and require fewer ammunition replenishments. However, the physical weight advantage of the round is misleading. The 5.56-mm NATO cartridge is approximately half the weight of the cartridge it replaced, the 7.62-mm NATO cartridge; a soldier can carry approximately twice as many 5.56-mm as 7.62-mm rounds. Although the two-to-one advantage is reduced substantially by the weight of the additional magazines, cartridge belts, and pouches needed for the additional ammunition, I will use that ratio here. In any case, it would be an advantage only if the 5.56-mm cartridge had the same one-round knockdown power as its predecessor—and the evidence demonstrates otherwise.
Field Test
The 5.56-mm cartridge was produced from the Remington .223-caliber commercial round that is advertised for use in groundhog and woodchuck hunting. In 1962, under the aegis of Project Agile, 1,000.223-caliber AR-15 Rifles were given to South Vietnamese soldiers for field testing. The cartridges were credited with scoring "instantaneous" one-shot kills. On 9 June, after ambushing an estimated Viet Cong (VC) company, a Ranger platoon reported five VC killed by the AR-15, with the following one-round lethal hits:
- Back wound, which caused the thoracic cavity to explode
- Stomach wound, which caused the abdominal cavity to explode
- Buttock wound, which destroyed all tissue of both buttocks
- Chest wound from right to left, which destroyed the thoracic cavity
- Heel wound, which was caused by a projectile entering the bottom of the right foot, causing the leg to split from the foot to the hip
All deaths were instantaneous, except for the buttock wound. The VC soldier with that wound lived about five minutes.
The Army Wound Ballistics Laboratory at Edgewood Arsenal was unable to confirm the Vietnam test reports by firing .223-caliber rounds into ballistic gelatin. The laboratory tried a second time using bullets with 1/4 inch cut off their tips and 3/32-inch-diameter holes drilled about 1/4 inch deep into the lead cores. The modified bullets also failed to duplicate the spectacular effects reported by Project Agile. Nonetheless, those unbelievable—and unconfirmed—results served as proof that the .223-caliber bullet had one-round knockdown power. The Department of Defense designated it as the 5.56-mm and made it the primary cartridge for U.S. shoulder weapons.2
Warriors' Reports
For more than 36 years, field reports from soldiers and Marines have provided ample evidence that challenges the basis for choosing the 5.56-mm cartridge:
Vietnam, 1965. According to the Army commander of the first U.S. unit to be engaged with major North Vietnamese Army (NVA) forces, "Even after being hit several times in the chest [with 5.56-mm rounds], many continued firing and moving for several more steps before dropping dead." Another infantry officer said, "In one fire fight, I saw my RTO [radio operator] place three rounds [of 5.56-mm] in the chest of a charging NVA regular at 50 yards. He kept firing his AK [Soviet AK-47 Assault Rifle] and never slowed down. At 30 yards, I hit him with a blast of double-ought buck. It picked him up off his feet and he didn't get up again."
Gulf War, 1991. A Marine officer reported that "several Marines commented that they had to shoot Iraqi soldiers 2-3 or more times with the 62-grain 5.56mm green tip ammo before they stopped firing back at them.... An Iraqi officer, still on fire, faced the firing line of Marines and charged forward firing his weapon from the hip. He didn't hit anyone, but two Marines each nailed him with a three-- round burst from their M-16A2s. One burst hit him immediately above his heart, the other in his belly button. [He] ... kept right on charging and firing until his magazine was empty.... The surgeons told me he certainly died of burns, but not necessary from the six 5.56-mm wounds."
Somalia, 1993. Army Sergeant First Class Paul Howe, a Delta Force soldier, noted that the 5.56-mm green-tip round made a small clean hole and passed right through the enemy. Unless it happened to hit the heart or spine, it was not enough to stop a man in his tracks. "Howe felt like he had to hit a guy five or six times just to get his attention."
Afghanistan, 2002. A soldier who preferred to remain anonymous e-mailed the following account to me in April 2002: "The current-issue 62-grain 5.56-mm (.223) round, especially when fired from the short-barreled, M-4 carbine, is proving itself (once again) to be woefully inadequate as [a] man stopper. Engagements at all ranges are requiring multiple, solid hits to permanently bring down enemy soldiers. Penetration is also sadly deficient. Even light barriers are not perforated by this rifle and cartridge combination."
These reports are consistent with my experience during three tours of duty in Vietnam from 1964 to 1969. It was apparent that the 5.56-mm cartridge was nothing more than the commercial Remington .223 cartridge used for hunting small game. (The state of Virginia does not permit it to be used for hunting deer because it cannot ensure a "clean kill" on deer.) Yet its full-metal-jacket military counterpart continues to be issued to U.S. combatants for the purpose of knocking down and killing or disabling enemy soldiers.
Unintended Consequences
By institutionalizing the proposition that volume fire is as effective as aimed fire, troops are encouraged to engage single targets with automatic fire and thus use even more ammunition. A Marine told me of an incident he witnessed during the Vietnam War: "In late 1966, I was on an OP [observation post] near Chu Lai with a squad of Marines at the time we transitioned to the M-16 (*&A%$ toy). With my binoculars I spotted an NVA courier replete with pouch walking on the edge of a paddy about 300 meters away, pith helmet with red star and all. Suggesting to the Lt. that he intercept the individual, he mistook that as a 'commence fire' command. The lads opened up and most of them had their new toys on full auto. I could see splashes and puffs all around said individual, who was now sprinting rapidly away. I ordered 'cease fire,' grabbed an M-14, sat, and drilled this guy with one shot at about 300 meters plus. ... Then I had the Marines police up the brass—168 rounds fired, one slight [5.56-mm] nick on the target."
Conclusions
Early judgments that the .223-caliber/5.56-mm round had one-round lethality against enemy soldiers have proved to be without merit. Soldiers and Marines from Vietnam to Afghanistan have witnessed enemy soldiers advancing and firing their weapons after being hit by several rounds of 5.56-mm ammunition. Further, it has been demonstrated repeatedly that the extra ammunition troops are able to carry as a result of the 5.56-mm's lighter weight does not add up to an increase in combat effectiveness. To the contrary, the evidence shows a loss of combat effectiveness overall because warriors need even more rounds than the two-for-one replacement effected by the change to the lighter round.
Replacing the 5.56-mm M-16A2 with a weapon chambered for the same cartridge only will perpetuate the round's deficiency and the increased logistic burden resulting from necessary and consequential higher volumes of fire.
Major Milavic, a former enlisted man, served both in infantry and intelligence assignments.