Armor Piercing 5.7x28mm Ammunition
There is a large amount of misinformation, mystery and speculation about the armor piercing capabilities of the 5.7x28mm cartridge.
The lack of clear, authoritative information on this topic can be laid partly at the feet of FN, who would like hype to drive sales of their products, but who are afraid of a public backlash simliar to the one surrounding the Black Talon. Perhaps also adding to the mystery is the ATF, who wish to be perceived as neither soft on enforcement nor overstepping their authority. In the cases of both FN and the ATF, the things that are not stated about the armor piercing capabilities of the 5.7x28mm cartridge are perhaps as revealing as the things that are. The rest of the problem is simply misinformation spread by word of mouth.
Here are some things to keep in mind:
- Ammunition that is not marketed as armor piercing may still be capable of penetrating some levels of body armor.
- Ammunition that is marketed as armor piercing may nevertheless be unable to penetrate some levels of body armor.
- There are several levels of body armor available and in use, and a given cartridge may penetrate some levels but not others.
- Barrel length has a significant effect on the velocity of a cartridge, and the results of penetration testing should be evaluated in terms of the barrel length (or velocity) that was used.
- Ammunition that is marketed as armor piercing may not be classified under Federal law as armor piercing, regardless of whether it is able to penetrate body armor or not.
- Nearly all centerfire rifle ammunition is able to penetrate most levels of body armor, regardless of its construction or classification.
In the United States, armor piercing handgun ammunition is illegal for civilians. However, what constitutes an armor piercing bullet (as defined by Federal law and the ATF) is often not what you might think. Specifically, the SS190 ammunition made by FN, which is voluntarily restricted to military and police sales, does not fit the Federal definition of armor piercing, regardless of how it is marketed.
Though armor piercing rifle ammunition is legal, Federal law does ban armor piercing ammunition for handguns [18 U.S.C. Section 922(a)(7)]. Essentially, it outlaws the manufacture, import or sale to civilians. A more careful reading is called for, but possession does not appear to be illegal.
The Federal definition of armor piercing ammunition [18 U.S.C. Section 921(a)(17)(B)] is important. It has nothing to do with testing of a cartridge's actual ability to penetrate body armor. The law classifies ammunition as being armor piercing based solely on its construction:
(i) a projectile or projectile core which may be used in a handgun and which is constructed entirely (excluding the presence of traces of other substances) from one or a combination of tungsten alloys, steel, iron, brass, bronze, beryllium copper, or depleted uranium; or
(ii) a full jacketed projectile larger than .22 caliber designed and intended for use in a handgun and whose jacket has a weight of more than 25 percent of the total weight of the projectile.
The SS190 cartridge, which has a steel penetrator and an aluminum core, does not fit this definition. A 5.7x28mm cartridge loaded with an FMJ bullet also does not fit this definition. A strict reading of Federal law indicates that neither the SS190 nor FMJ handloads are illegal for civilians.
Wikipedia has an informative article on the 5.7x28mm cartridge, which includes a run-down of each type of factory ammunition. In it, they reference an ATF statement on the cartridge. The Wikipedia article uses this reference to suggest that the ATF has classified certain cartridges as being armor piercing. However, I read it differently.
In the statement, the ATF makes it clear that their classification can only coincide with the Federal definition of armor piercing ammunition. They go on to say that the SS196 has been examined by the Firearms Technology Branch and has determined that SS196 is not classified as armor piercing. They go on to relate FNH's findings about what levels of body armor the SS192 and SS196 cartridges did not penetrate during their testing. They also repeat FNH's assertion that they have voluntarily restricted commercial sale of SS190 ammunition.
The ATF statement ends with a list of factory loadings of the cartridge, including their designation and their descriptions. Several cartridges are listed as being AP or not AP. The Wikipedia article has apparently inferred this to be a classification by the ATF. However, I contend that it is not. The only classification stated was that SS196 was not armor piercing ammunition according to Federal law.
Classification of Body Armor
The most broadly accepted standard for classification of personal body armor is NIJ Standard-0101.06. Type IIA, II, and IIIA (from lowest protection to highest) are tested against handgun ammunition. Type III and IV are tested against rifle ammunition.
The SS190 cartridge has a 32 grain full metal jacket bullet with a steel penetrator and an aluminum core. It is apparently designed to be armor piercing, and is marketed as such by FN.
Other than to list FN's designation for this cartridge as being an armor piercing round, the ATF's statement does not declare SS190 to fall under the Federal defintion of armor piercing ammunition. While the bullet does contain a steel penetrator, and the penetrator could be argued to be part of the core, the core cannot be said to be "constructed entirely" of metals listed in the Federal definition. Therefore, any sensible reading of the law must conclude that SS190 cannot be classified as armor piercing ammunition under Federal law.
This is confusing because FN designates and markets SS190 as armor piercing, and because sale of SS190 is restricted to military and law enforcement customers. However, this restriction is voluntary on the part of FN. The restriction is evidently enforced under ATF rules.
Published penetration tests for the SS190 cartridge are scant. The RCMP conducted tests with a P90 (which has a 10½" barrel), which determined that the cartridge was able to penetrate a Type II vest. The Houston Police Department has written of it's capability to "defeat level IIIA body armor at 200 meters", but it is unclear whether they did the testing or were repeating someone else's results, nor did they describe the firearm used in testing.
In October 2013, a writer for The Firearm Blog conducted some actual tests (with nice pictures) against soft body armor. They were able to penetrate Type IIIA soft body armor with SS190 fired from a handgun and with SS197 fired from a rifle with a 16" barrel.
The SS192 cartridge is manufactured with a 28 grain hollow point bullet with a copper jacket and an aluminum core. Bullets of this design are generally considered target bullets.
The ATF's statement is unclear, but it is obvious that this bullet cannot fit the Federal definition of armor piercing ammunition.
FN claims that SS192 did not penetrate Type IIIA vests. However, the barrel length, and therefore the velocity, was not stated. Also not stated was whether SS192 was able to penetrate less resistant Types IIA and II body armor.
SS192 is no longer being imported, and has been replaced with SS195. The SS195 cartridge appears to be the same as SS192, but with a lead-free primer. One can assume that SS192 and SS195 have essentially the same penetrating capability.
The SS196 cartridge is manufactured with a 40 grain Hornady V-Max bullet. This bullet has a lead core, a copper jacket, and a plastic tip, and it is designed to disintegrate rapidly upon impact.
The ATF has specifically stated that SS196 does not fit the Federal definition of armor piercing ammunition.
FN claims that SS196 fired from a 4¾" barrel did not penetrate Type II vests during their testing. Note that this claim does not indicate the capability of the cartridge when fired from a 10½" (P90) or 16" (PS90) barrel. Indeed, the test of SS197 published by The Firearm Blog showed that it could penetrate Type IIIA soft body armor when fired from a rifle with a 16" barrel. Also note that FN's claim does not discuss the effectiveness of less resistant Type IIA body armor.
The SS197 cartridge is the same as the SS196, except that it is loaded to slightly higher velocity and has a blue tip. I have not seen the results of any penetration testing for the SS197, but one can assume that SS196 and SS197 have very similar penetrating capability.