FN 5 . 7×28mm The FN 5 . 7×28mm is a small - caliber , high - velocity cartridge designed and manufactured by FN Herstal in Belgium . It is a bottlenecked centerfire cartridge that is somewhat similar to the . 22 Hornet or . 22 K - Hornet . The 5 . 7×28mm was developed in conjunction with the FN P90 personal defense weapon ( PDW ) and FN Five - seven pistol , in response to NATO requests for a replacement for the 9×19mm Parabellum cartridge . In 2002 and 2003 , NATO conducted a series of tests with the intention of standardizing a PDW cartridge as a replacement for the 9×19mm Parabellum cartridge . The tests compared the relative merits of the 5 . 7×28mm cartridge and the 4 . 6×30mm cartridge , which was created by Heckler & Koch as a competitor to the 5 . 7×28mm . The NATO group subsequently recommended the 5 . 7×28mm cartridge , citing superior performance in testing , but the German delegation objected and the standardization process was indefinitely halted . By 2006 , FN ' s 5 . 7×28mm firearms — the P90 personal defense weapon and Five - seven pistol — were in service with military and police forces in over 40 nations throughout the world . In the United States , 5 . 7×28mm firearms are currently used by numerous law enforcement agencies , including the U . S . Secret Service . In addition to being used in the FN P90 and FN Five - seven firearms , the 5 . 7×28mm cartridge has subsequently been used in a number of other weapons , such as the AR - 57 and FN PS90 carbines . Excel Arms has developed four firearms chambered in 5 . 7×28mm , and MasterPiece Arms offers three different 5 . 7×28mm firearms . The 5 . 7×28mm cartridge itself is produced in a number of varieties , two of which — the SS195LF and SS197SR — are currently offered by FN to civilian shooters for use in 5 . 7×28mm firearms . History . Development . The 5 . 7×28mm cartridge was designed in response to NATO requests for a replacement for the 9×19mm Parabellum cartridge . According to the NATO requirement , the new cartridge was to have greater range , accuracy , and terminal performance than the 9×19mm cartridge . Additionally , it was to be capable of penetrating body armor . FN Herstal responded to the NATO requirement by developing the 5 . 7×28mm cartridge and two associated weapons : the FN P90 personal defense weapon ( PDW ) and FN Five - seven pistol . The original 5 . 7×28mm cartridge , called the " SS90 " , was introduced in 1990 . It used a 1 . 5 g ( 23 grain ) plastic - core projectile , which it propelled at a muzzle velocity of roughly 850 m / s ( 2 , 800 ft / s ) when fired from the P90 . A United States patent application for the projectile design used in the SS90 was filed by FN ' s Jean - Paul Denis and Marc Neuforge in 1989 . " U . S . Patent 5 , 012 , 743 " ( " High - Performance Projectile " ) was received in 1991 . The 5 . 7×28mm SS90 cartridge was discontinued , and replaced in 1993 with the 5 . 7×28mm SS190 . The SS190 uses a 2 . 7 - mm ( 0 . 11 in ) shorter projectile with a weight of 2 . 0 g ( 31 grains ) , which it fires from the P90 at a muzzle velocity of roughly 715 m / s ( 2 , 350 ft / s ) . The shorter length of the SS190 projectile allowed it to be more conveniently used in the 5 . 7×28mm FN Five - seven pistol , which was also being developed at that time . In 1993 , FN introduced a modified version of the P90 with a magazine adapted to use the SS190 cartridge . Several specialized 5 . 7×28mm varieties were also developed alongside the SS190 , such as the L191 tracer round and the subsonic SB193 bullet for sound - suppressed use . The 5 . 7×28mm FN Five - seven pistol then went into production in 1998 . NATO evaluation . In 2002 and 2003 , NATO conducted a series of tests with the intention of standardizing a PDW cartridge as a replacement for the 9×19mm Parabellum cartridge . The tests compared the relative merits of the 5 . 7×28mm cartridge and the HK 4 . 6×30mm cartridge , which was created by German small arms manufacturer Heckler & Koch as a competitor to the 5 . 7×28mm . The results of the NATO tests were analyzed by a group formed of experts from Canada , France , the United Kingdom , and the United States , and the group ' s conclusion was that the 5 . 7×28mm was " undoubtedly " the more efficient cartridge . Among other points , the NATO group cited superior effectiveness ( 27 percent greater ) for the 5 . 7×28mm against unprotected targets and equal effectiveness against protected targets . It also cited less sensitivity to extreme temperatures for the 5 . 7×28mm , and cited a greater potential risk of barrel erosion with the 4 . 6×30mm . In addition , the group pointed out that 5 . 7×28mm is close to the 5 . 56×45mm NATO by its design and manufacture process , allowing it to be manufactured on existing production lines . The group also pointed out that 5 . 7×28mm firearms are more mature than 4 . 6×30mm firearms , and that the 5 . 7×28mm FN Five - seven pistol was already in production at that time , while the 4 . 6×30mm Heckler & Koch UCP pistol was only an early concept . However , the German delegation and others rejected the NATO recommendation that 5 . 7×28mm be standardized , halting the standardization process indefinitely . As a result , both the 4 . 6×30mm and 5 . 7×28mm cartridges ( and the associated weapons ) have been independently adopted by various NATO countries , according to preference ; both the P90 and Five - seven are currently in service with military and police forces in over 40 nations throughout the world . Present . In 2004 , the " SS192 " hollow - point cartridge was introduced to civilian shooters alongside the new " IOM " variant of the Five - seven pistol . After being met with controversy , the SS192 variety was discontinued in the same year , and in 2005 the " SS196SR " variety was introduced using a 2 . 6 g ( 40 grain ) Hornady V - Max projectile . The SS196 was also shortly discontinued in favor of the newer SS195LF and SS197SR varieties , which are currently offered to civilian shooters for use in 5 . 7×28mm firearms , followed by the SS198LF variety , which is currently produced but is restricted by FN to military and law enforcement customers . FN ' s 5 . 7×28mm ammunition types were briefly manufactured by Olin - Winchester , but today they are only made by FN Herstal in Belgium and ( since 2006 ) Fiocchi in the United States . In 2009 , the National Rifle Association added 5 . 7×28mm firearms to its NRA Tactical Police Competition standards , allowing law enforcement agencies to compete in this event using 5 . 7×28mm firearms . Starting in 2012 , Federal began producing a new 5 . 7×28mm round for civilian shooters , designated the " AE5728A " . Design details . The 5 . 7×28mm cartridge was designed by FN Herstal specifically for use in the FN P90 personal defense weapon and FN Five - seven pistol . Subsequently , it has been used in a number of other weapons , such as the FN PS90 carbine and the AR - 57 , an upper receiver for M16 / AR - 15 rifles . The ST Kinetics CPW can be configured for the 5 . 7×28mm cartridge by changing the barrel and magazine groups . Excel Arms has developed four firearms chambered in 5 . 7×28mm , and MasterPiece Arms offers three different 5 . 7×28mm firearms . The 5 . 7×28mm cartridge weighs 6 . 0 g ( 93 grains ) — roughly half as much as a typical 9×19mm Parabellum cartridge — making extra ammunition less burdensome , or allowing more ammunition to be carried for the same weight . Since the 5 . 7×28mm cartridge also has a relatively small diameter , an unusually high number of cartridges can be contained in a magazine . The cartridge has a loud report and produces considerable muzzle flash ( when fired from a pistol ) , but it has roughly 30 percent less recoil than the 9×19mm cartridge , improving controllability . Due to its high velocity , the 5 . 7×28mm also exhibits an exceptionally flat trajectory . One of the design intents of the SS190 variety of this cartridge was that it have the ability to penetrate Kevlar protective vests — such as the NATO CRISAT vest — that will stop conventional pistol bullets . Fired from the P90 , the SS190 is capable of penetrating the CRISAT vest at a range of 200 m ( 219 yd ) , or a Level IIIA Kevlar vest at the same range . However , sporting variants of the 5 . 7×28mm are classified by the U . S . Bureau of Alcohol , Tobacco , Firearms and Explosives ( ATF ) as not armor - piercing . According to FN , the 5 . 7×28mm cartridge has an effective range of 200 m ( 219 yd ) and a maximum range of 1 , 800 m ( 1 , 969 yd ) when fired from the P90 , and an effective range of 50 m ( 55 yd ) and a maximum range of 1 , 510 m ( 1 , 651 yd ) when fired from the Five - seven . In testing , the SS190 and similar 5 . 7×28mm projectile s consistently turn base over point ( " tumble " ) as they pass through ballistic gelatin and other media , using the 21 . 6 - mm ( . 85 in ) projectile length to create a larger wound cavity . However , some are skeptical of the bullet ' s terminal performance , and it is a subject of debate among civilian shooters in the United States . The 5 . 7×28mm projectile potentially poses less risk of collateral damage than conventional pistol bullets , because the projectile design limits overpenetration , as well as risk of ricochet . The lightweight projectile also poses less risk of collateral damage in the event of a miss , because it loses much of its kinetic energy after traveling only 400 m ( 437 yd ) , whereas a conventional pistol bullet such as the 9×19mm retains significant energy beyond 800 m ( 875 yd ) . This range exceeds the engagement distances expected for the 5 . 7×28mm cartridge ' s intended applications , so the cartridge ' s limited energy at long range is not conversely considered to be disadvantageous . Since the 5 . 7×28mm SS190 projectile does not rely on fragmentation or the expansion of a hollow - point bullet , the cartridge ( and 5 . 7×28mm firearms ) are considered suitable for military use under the Hague Convention of 1899 , which prohibits the use of expanding bullets in warfare . FN ' s 5 . 7×28mm cartridge cases are covered with a special polymer coating for easier extraction with the PS90 carbine due to the high chamber pressures and lack of case tapering . In addition , this coating ensures proper feeding and function in the magazines . Cartridge dimensions . 5 . 7×28mm maximum CIP cartridge dimensions . All sizes in millimeters ( mm ) . The 5 . 7×28mm has a cartridge case capacity of 0 . 90 ml ( 13 . 85 grains HO ) . Americans define the shoulder angle at alpha / 2 ≈ 35 degrees . The common rifling twist rate for this cartridge is 1 : 228 . 6 mm ( 1 : 9 in ) , 8 grooves , Ø lands = 5 . 53 mm , Ø grooves = 5 . 62 mm , land width = 1 . 63 mm and the recommended primer type is small rifle . According to the official Commission Internationale Permanente pour l ' Epreuve des Armes à Feu Portatives ( CIP ) guidelines the 5 . 7×28mm case can handle up to 345 MPa ( 50 , 037 psi ) piezo pressure . In CIP - regulated countries every rifle cartridge combo has to be proofed at 125 % of this maximum CIP pressure to certify for sale to consumers . Specifications . Fired from the longer 40 . 74 - cm ( 16 . 04 in ) barrel of the PS90 , the muzzle velocity of SS195LF is roughly 60 - m / s ( 200 ft / s ) faster , and the muzzle velocity of SS197SR is roughly 45 - m / s ( 150 ft / s ) faster . Fired from the shorter 12 . 2 - cm ( 4 . 8 in ) barrel of the Five - seven pistol , the muzzle velocity of SS195LF is roughly 90 - m / s ( 300 ft / s ) slower , and the muzzle velocity of SS197SR is roughly 60 - m / s ( 200 ft / s ) slower . Controversy . The FN Five - seven pistol and FN 5 . 7×28mm ammunition were originally restricted by FN to military and law enforcement customers , but in 2004 the new " Five - seven IOM " variant was introduced , and offered to civilian shooters for use with SS192 ammunition . FNH USA has marketed the Five - seven to civilian shooters as a pistol suitable for personal protection , target shooting , and similar uses , but the Five - seven ' s introduction to civilian shooters was strongly opposed by U . S . gun control organizations such as the Brady Campaign ; by the end of 2004 , sales of the Five - seven pistol had increased dramatically . In early 2005 , the pistol was subject to intense controversy in the United States after the Brady Campaign stated that commercially available SS192 ammunition penetrated a Level IIA Kevlar vest in testing . The National Rifle Association ( NRA ) shortly countered the Brady Campaign ' s claim by stating that the gun control group may not have adhered to standard testing procedures , and that FN only offers armor - piercing varieties of the 5 . 7×28mm cartridge to military and law enforcement customers . Varieties offered to civilians are classified by the U . S . Bureau of Alcohol , Tobacco , Firearms and Explosives ( ATF ) as not armor - piercing , and it was stated that the SS192 and SS196 cartridge variations were unable to penetrate various types of Kevlar vests in tests conducted by FNH USA . Michael D . Barnes , then - president of the Brady Campaign , responded to the NRA ' s statements on the Five - seven by challenging NRA Executive Vice President Wayne LaPierre to be shot with the pistol while wearing a Kevlar vest . The NRA again attacked the Brady Campaign ' s statements , saying that " Barnes demonstrated his group ' s complete and utter disregard for gun safety and its flaming zeal to further restrict the rights of law - abiding gun owners . " In the same year , two pieces of legislation were introduced in the United States Congress , specifically targeting the Five - seven pistol and 5 . 7×28mm ammunition for a federal ban : the " H . R . 1136 : PLEA Act " was introduced in the House of Representatives by Rep . Eliot Engel ( D - NY ) , and the " S . 527 : PLEA Act " was introduced in the Senate by Sen . Frank Lautenberg ( D - NJ ) ; neither bill proceeded to a vote by the House or Senate . In March 2007 , legislation was again introduced in the United States Congress by Rep . Engel , under the new designation " H . R . 1784 : PLEA Act " . Once again , the bill failed to proceed to a vote . In the following years , the Five - seven was subject to further controversy due to reports of the pistol ' s use by drug cartel s in the Mexican Drug War . In the United States , the Five - seven has never been used to kill a police officer , but various news sources such as " The Boston Globe " and " La Jornada " reported incidents in which the pistol was used to shoot and kill police officers or civilians in Mexico . According to the ATF , the Five - seven is one of the weapons favored by drug cartels in the Mexican Drug War , and smuggled Five - seven pistols can sell for up to $ 5 , 000 in Mexico . From Mexico , the pistols have been smuggled into other South American countries ; in a July 2010 drive - by shooting in Envigado , Colombia , two cartel gunmen armed with Five - seven pistols opened fire on a group of bystanders outside a nightclub , leaving 9 people dead and 10 wounded . In November 2009 , the Five - seven again became subject to intense controversy in the United States , following the Fort Hood shooting at Fort Hood military base , in Texas . A U . S . Army psychiatrist , Major Nidal Malik Hasan , opened fire on fellow soldiers with a Five - seven pistol , killing 13 and wounding 29 in the worst shooting ever to take place on an American military base . Shortly after the shooting , FNH USA responded with a fact sheet dismissing allegations about the nature of the pistol , stating that it is only offered to civilians with sporting ammunition . Later in the month , a number of gun control organizations such as the Brady Campaign wrote a collaborative letter to U . S . President Barack Obama , citing the weapon ' s reported use by the Fort Hood shooter and Mexican drug cartels , and calling on him to ban importation of the Five - seven pistol and 5 . 7×28mm ammunition . In July 2010 , legislation was introduced in the United States Congress by Rep . Engel , for a third time , under the new designation " H . R . 6030 : PLEA Act " . Like its previous incarnations , the " H . R . 6030 " bill failed to proceed to a vote by either the House of Representatives or Senate .