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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.
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.
The FBI study clearly demonstrates the following: (1) that .223 rounds on average, penetrate less than the hollow point pistol rounds evaluated, (2) concern for overpenetration of the .223 round, at close range, has been greatly exaggerated, (3) with the exception of soft ballistic garment penetration, the .223 round appears to be relatively safer for employment in CQB events than the hollow point bullets tested