.223 for CQB
by R.K. Taubert
About the author: A recently retired FBI Agent with over 20 years experience in SWAT and Special Operations, he conducted extensive counter-terrorism and weapons research while in the Bureau.
Reprinted and edited with permission.
Close Quarter Battle Reputation
Several interesting but inconclusive articles examining the feasibility of the .223 caliber, or 5.56x45mm round, for CQB events, such as hostage rescue and narcotics raids, have recently been featured in a variety of firearms and police publications. However, for more than 20 years, conventional law enforcement wisdom generally held that the .223 in any configuration was a deeply penetrating round and, therefore, totally unsuited for CQB missions in the urban environment. Partly because of this erroneous, but long held perception, and other tactical factors, the pistol caliber submachine gun (SMG) eventually emerged as the primary shoulder "entry" weapon for the police and military SWAT teams.
Although new revelations about the .223 are beginning to slowly circulate throughout the Special Operations community, a number of law enforcement agencies are in the process of acquiring the next generation of "advanced" SMGs in 10mm and .40 S&W calibers. Could they and the public be better served by a .223 caliber weapons system and at less expense? Please read on and judge for yourself.
FBI Ballistic Tests
As a result of renewed law enforcement interest in the .223 round and in the newer weapons systems developed around it, the FBI recently subjected several various .223 caliber projectiles to 13 different ballistic tests and compared their performance to that of SMG-fired hollow point pistol bullets in 9mm, 10mm, and .40 S&W calibers.
Bottom Line: In every test, with the exception of soft body armor, which none of the SMG fired rounds defeated, the .223 penetrated less on average than any of the pistol bullets.
These tests were conducted by the FBI’s Firearms Training Unit (FTU), at the request of the Bureau Tactical and Special Operations personnel. Located at the FBI academy in Quantico, VA, this is the same unit with the encouragement of forensic pathologist Dr. Martin Fackler and other ballistic experts, that dramatically advanced the testing of modern handgun rounds to estimate their wounding effectiveness and potential lethality. Ultimately, this entity confirmed that permanent crush cavities, or "wound-channels," and deep penetration were the primary factors for handgun-fired projectiles. The FTU further determined that under various target engagement circumstances, a depth of penetration in soft tissue of between 12 to 18 inches was required for a handgun bullet to be effective.
Equipment Employed / Rounds Tested
For these series of tests the following firearms, ammunition and equipment were employed:
• Sealed, match grade test barrel to determine 25 yard, 10-shot group accuracy and 20-round velocity potential.
• 20" barreled, M16A1 rifle to stabilize and test rounds ranging from 40 to 55 grains in weight.
• 20" barreled, M16A2 rifle to stabilize and test rounds ranging from 62 to 69 grains in weight.
• Oehler Model 85 chronograph.
• Ransom type rifle rest, with laser bore sighting.
• Numerous blocks of Kind and Knox 250-A, 10% gelatin, to simulate living tissue.
• Federal’s 40-grain "Blitz" hollow point, 55-grain soft point and 69-grain hollow point; 9mm 147-grain Hydra-Shok, 10mm and .40 S&W 180-grain, jacketed hollow points.
• Winchester’s 55- and 62-grain full metal case, NTO-military spec. rounds.
As indicated, both rifles were fired from a mechanical rest. Ten-shot groups and 20-round velocity tests were fired for each round. 13 penetration tests were conducted. 95 rounds were fired for each type of round tested. A total of 760 rounds were tested and recorded for this project.
Test Protocol
Tests 1-6:
Bare gelatin, heavy clothing, automobile sheet metal, wallboard, plywood, and vehicle windshield safety glass, were shot a distance of 10 feet from the muzzle. The vehicle safety glass was set at an angle of 45 degrees to the horizontal, with the line of bore of the rifle/SMG offset 15 degrees to the side resulting in a compound angle of impact for the bullet upon the glass, which simulates a shot directed at the driver of a car closely missing the shooter. Furthermore, the gelatin was covered with light clothing and set back 18 inches behind the glass. All gelatin blocks, with the exception of the body armor barrier, were set 18 inches behind each solid obstacle shot.
Tests 7-13:
All involved shots through heavy clothing, safety glass and bare gelatin at 50 to 100 yards, concluding with internal walls, external walls and body armor at 10 feet. Test eight however, involved safety glass at 20 yards, shot dead-on, without the 15 degree offset, to simulate a shot at a car’s driver bearing down on the shooter.
For the connivance of the reader, test results are summarized in the following chart. Please note that the data displayed represents the average penetration of these rounds as measured in 10% ballistic gelatin (see tables 1 and 2).
Considering that the average person’s torso is 9 inches thick, front to back, all the .223 rounds ranging in weight from 55 to 69 grains appear to be adequate performers on soft targets where frontal shots are involved. Although the majority of target engagements are frontal, profile shots can and do occur. A .223 round that is required to pass through an arm before entering the rib cage mat, upon striking bone, fragment, and while possibly shattering the appendage, would most likely not be successful in producing a sufficiently deep body cavity wound to be decisive. In this, as with any CQB encounter, "controlled pairs," or rapid-repeat hits may be required to ensure target neutralization.
Defeating Ballistic Garments
Soft body armor appears to have little effect on the calibers ability to penetrate and actually seemed to enhance the 40-grain Blitz’s depth of penetration in soft tissue.
From a law enforcement standpoint, the ability of the .223 caliber round to defeat soft body armor, military ballistic helmets and many ballistic shields is a "double-edged sword." The criminal use of body armor is rare, but increasing. Possessing the ability to penetrate and adversary’s protective vest is obviously desirable. However, this round will also defeat law enforcement vests, so great care must be exercised in laying out and observing fields of fire in training and during operations. With this concern over potential fratricide in mind, voices have been raised in some quarters regarding this bilateral tactical attribute. A number of veteran officers strongly embrace The traditional concept that a department’s duty rounds should not exceed the capabilities of their vests. Arguably, this is a sound approach for any law enforcement agency to take for its non-tactical response personnel. However, SWAT, because of its specialized missions, may be a different matter and this later concern, while important, should not dominate the rationale supporting weapons selection by highly competent tactical units.
Although it has been reported that less that 1% of all serious crimes involve long guns and less than 8% of long gun related crimes involve rifles, law enforcement is being confronted more frequently by criminals with weapons and munitions that are capable of defeating all but the heaviest ballistic protection. The FBI’s Uniform Crime Reporting Section indicates, for example, that rifles were involved in 13% of the assaults on police officers during 1992. The incident a Waco, Texas, is a recent example of this problem. For forced entry teams, the need for higher levels of ballistic protection is essential.
For safe training of specialized law enforcement teams, the development of a lead-free, low penetration, short-range 5.56mm/.223 caliber training round that will (1) not penetrate ballistic vests and helmets, (2) destroy "shooting house" walls, (3) crater, or perforate steel-reactive targets, is extremely important. Fortunately, it appears that private industry is responding to these demands and such munitions are currently being developed.
Vehicle Interaction
With the exception of the full metal case and the 69-grain JHP rounds, it appears inadvisable to select lighter weight, soft or hollow point versions of this caliber when automobiles are likely to be engaged during planned raids and arrests. Penetration against automobile windshield safety glass is generally very poor and is only slightly better on sheet steel. Although terrorists from the insurgent New Peoples’ Army were able to blast their way through an armored limousine in the Philippines and murder a highly regarded U.S. military official with concentrated M-16 rifle fire, the SMG-fired pistol round demonstrates at least a theoretical, if not practical, edge against such hardened targets.
Interestingly, while penetration on auto glass and sheet steel is marginal, .223 projectiles will readily perforate and breach mild steel such as standard pepper poppers, that pistol rounds will only slightly dimple. However, very little of the .223’s mass is retained, so after defeating mild steel, significant wound potential is severely diminished upon exit.
Barriers and Structures
The Bureau’s research also suggests that common household barriers such as wallboard, plywood, internal and external walls are also better attacked with pistol rounds, or larger caliber battle rifles, if the objective is to "dig out" or neutralize people employing such object as cover or concealment. Although it is usually not advisable to fire at targets you can’t see in urban settings, it is done and some subjects have been stopped in this manner. Conversely, the ability of some pistol rounds to penetrate barriers tested puts innocent bystanders and fellow team members at greater risk in CQB scenarios. If an operator misses the intended target, the .223 will generally have less wounding potential than some pistol rounds after passing through a wall or similar structure. The close range penetration tests conducted indicated that high velocity .223 rounds were initially unstable and may, depending on their construction, disintegrate when they strike an object that offers some resistance. When concrete, brick or macadam are struck at an angle at close range, .223 rounds tent to fragment or break up, and ricochets are generally less hazardous. The .223 could consequently be considered safer for urban street engagements, because of its inherent frangibility within the cross-compartments created by street environments. In other words, in most shootings, the round would probably strike something, hopefully a hard object, break up and quickly end its potentially lethal odyssey.
As a point of interest, the rifled shotgun slug, while not possessing the .223’s flat trajectory, is still capable of attaining a maximum range of 900 yards. This fact illustrates that any errant law enforcement round regardless of caliber, or maximum range, is potentially dangerous to the community.
.223 Wounding Characteristics
Ballisticians and Forensic professionals familiar with gunshot injuries generally agree that high velocity projectiles of the .223 genre produce wounds in soft tissue out of proportion to their calibers, i.e. bullet diameter. This phenomenon is primarily attributed to the synergistic effects of temporary stretch cavity (as opposed to the relatively lower velocity stretching which typifies most pistol rounds) and bullet fragmentation on living tissue.
Distinguished forensic pathologist Dr. Martin L. Fackler, observed when he was conducting wound research for the U.S. Army several years ago ("Wounding Patterns of Military Rifles," International Defense Review, Volume 22, January, 1989), that in tissue simulants such as ballistic gelatin, , the 55-grain, M-193 military bullet lost stability, yawed (turned sideways) 90 degrees, flattened and broke at the cannelure (groove around
