Tactical Briefs #4, 1 April 1998
GUN TESTS Magazine Unqualified to Evaluate Personal Defense Ammunition
Weve reviewed a couple articles recently published in GUN TESTS Magazine in which they attempted to evaluate the performance of various personal-defense handgun cartridges. Our conclusion after reading these articles is that the staff of GUN TESTS is wholly unqualified to perform meaningful and valid wound ballistics testing. They have absolutely no clue as to what theyre doing, and this is demonstrated by their lack of knowledge about wound ballistics in general, their test methodology and their interpretation of ballistic gelatin test results.
"Performance Test: 9mm Handgun Ammunition." GUN TESTS, August 1996, has been reprinted on the Cor-Bon web site. (We provide a link to this page at the end of this article.) Although the article is almost two years old, we came across a similar GUN TESTS article last summer and it contained identical defects. ("Cor-Bon 185-grain +P, 165-grain +P JHPs Beats Other .45 ACP Ammunition," Gun Tests, 7/97, pages 25-30).
Upon reading the article, its immediately evident GUN TESTS doesnt understand the mechanisms that are producing the results theyre observing. They use the vague term "cavity" in describing gelatin disruption. Readers are told that a .44 Magnum softpoint bullet "...left only a small cavity," whilst a 9mm Glaser "...left a much larger cavity." The reader is left to wonder if theyre describing permanent cavity (the hole made by the bullet) or temporary cavity (the cracks in the gelatin produced by the temporary cavity)?
They also use the nonstandard term "shredding" to describe gelatin disruption produced by a passing bullet. We believe this to mean the cracks in the gelatin created by the temporary cavity. Unfortunately, they seem to believe the disruption that theyre observing in gelatin will be reproduced in the human body as physical damage to soft tissues, and this is not true.
The cracks and "shredding" are produced when the temporary cavity stretches the gelatin beyond the limits of its elasticity and the gelatin tears. These tears and "shredding" are in no way representative of the damage a bullet will create in the human body. The majority of human soft tissues can easily withstand the stretching of temporary cavitation produced by most handgun bullets without tearing.
The corner of a block of gelatin and be torn off with little effort using bare hands only. Pushing a fingertip into gelatin can produce cracks. Neither of these two examples of gelatin disruption are representative of the kind of damage that is reproducible in the human body using the same means.
GUN TESTS tells readers: "To be effective, a bullet must transfer its kinetic energy to the target. To do this, it must slow down in the target. Expansion or mushrooming causes most of this deceleration." This unsupported statement is false. According to GUN TESTS it doesnt matter whether or not the bullet damages vital tissues to be effective, rather it simply has to magically "transfer energy". We offer this advice: anyone who uses the term "energy transfer" as a means to describe handgun ammunition wounding effectiveness is uninformed and simply does not know what he or she is talking about. We addressed the myth of energy transfer in detail in a previous Tactical Briefs.
The bizarre test fixture in which the bullet is fired into a gelatin block and recovered from water doesnt allow GUN TESTS to observe the entire wound track. Readers are told that the 9-inch depth of the block of ordnance gelatin was "...chosen to duplicate the body. We wanted the bullets to exit as they normally would, rather than expend more of their energy in a deeper than normal medium." Whos body are they attempting to duplicate? Is it a human body? A goat body? The body of a 200 pound adult male attacker? How did they arrive at the conclusion that a 9-inch deep block of gelatin accurately or reasonably represents a human body? They dont tell us.
Several years ago, a wound ballistics researcher noticed that during autopsy of fatal gunshot victims bullets were routinely found just underneath the skin at the expected point of exit. The bullets wound track simply ended just below the skin. Subsequent investigation revealed that unshored skin where the bullet would normally exit the body offers great resistance to bullet passage. In order to pass through, a bullet must overcome the elasticity of the skin and tear the skin to exit. Researchers found that in order for a bullet to exit skin, it must possess the equivalent momentum required to penetrate approximately four inches of muscle tissue. What this means is, in order for a bullet to pass completely through a human torso that is 11 inches deep, the bullet must be capable of penetrating at least 15 inches or more of soft tissue.
This hold-back effect of the skin has been observed in shootings. One shooting involved a gang member whod been accidentally shot in the neck by a 9mm 124 grain Federal JHP bullet. The bullet passed through about 5 inches of soft tissue in the victims neck, exited near his shoulder and continued on to strike his girlfriend in her back. The expanded bullet was recovered when paramedics began treating the girlfriend, and the bullet simply fell out of the superficial wound and onto the floor. The bullet from this particular cartridge normally penetrates approximately 9 inches of standard gelatin.
Skin plays a role in bullet exit, not bullet entry. When a bullet enters the body, it crushes a hole in skin. However, when a bullet exits the body, it tears unshored skin (skin that is not in contact with a backing object). To prove this to yourself, the next time you are getting ready to open a package of ground beef for a meal, press your index finger into the plastic wrapping that is in contact with the meat. You wont have to press too far before your finger puts a hole through the wrapping. Next, after youve removed the plastic wrap, try to poke your index finger through a single layer with no backing. Youll notice that the plastic wrap will stretch much further than it did the first time before your finger pops through. This simple experiment involving plastic food wrapping is analogous to the role skin plays in retaining a bullet inside the body.
The GUN TEST staff also evaluated a few pre-fragmented bullet cartridges. They apparently have the misunderstanding that these "safety slugs" are designed to minimize penetration of sheetrock walls. Only the MagSafe SWAT cartridge is specifically designed to limit wall penetration. All the others tested are designed for limited penetration of the human body.
The top rated cartridges of the GUN TESTS evaluation are incapable of reliably penetrating deeply enough from any angle to crush a hole in vital cardiovascular structures. These cartridges are rated as effective because the staff of GUN TESTS is preoccupied with velocity and energy transfer, not wound trauma.
One interesting inconsistency we noticed in reading the GUN TESTS article is where they mention their consideration of selected bullets for hunting bear and state: "Good hunting bullets retain their weight in order to penetrate." Yet in their conclusion they state that they wouldnt want to use any of the deepest penetrating bullets they tested on "...anything that could bite, claw or shoot back." Hmmmm..., apparently the kinds of bullets needed to stop dangerous wild animals must be somehow different from the kinds of bullets needed to stop dangerous humans. Must be that inexplicable energy transfer thing.
The staff of GUN TESTS performed a series of useless tests based on disproven junk-science which produced absurd results and dangerous recommendations. For a magazine that proclaims itself to be "the consumer reports of the shooting industry" the staff and editor appear to have absolutely no idea what theyre doing when it comes to wound ballistics testing. GUN TESTS clearly is neither a Consumer Reports nor an Underwriters Laboratory. GUN TESTS seems to be completely unfamiliar with the concept of scientific method.
Before GUN TESTS attempts any future handgun ammunition performance testing, the editor and staff need to learn a great deal about the basics of wound ballistics in order to be credible. Theyre amateurs who dont know what theyre doing. Their "findings" and "recommendations" can get good people killed.
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