FN Five - seven The FN Five - seven , trademarked as the Five - seveN , is a semi - automatic pistol designed and manufactured by FN Herstal in Belgium . The pistol is named for its 5 . 7 - mm ( . 224 in ) bullet diameter , and the trademark capitalization style is intended to emphasize the manufacturer ' s initials — " FN " . The Five - seven pistol was developed in conjunction with the FN P90 personal defense weapon and the FN 5 . 7×28mm cartridge . The P90 was introduced in 1990 , and the Five - seven was introduced in 1998 as a pistol using the same 5 . 7×28mm ammunition . Developed as a companion pistol to the P90 , the Five - seven shares many of its design features : it is a lightweight polymer - based weapon with a large magazine capacity , ambidextrous controls , low recoil , and the ability to penetrate body armor when using certain cartridge types . Sales of the Five - seven were originally restricted by FN to military and law enforcement customers , but since 2004 , the pistol has also been offered to civilian shooters for personal protection , target shooting , and similar uses . Although offered only with sporting ammunition , the Five - seven ' s introduction to civilian shooters was met with vocal opposition from gun control organizations such as the Brady Campaign , and the pistol has been subject to ongoing controversy in the United States . The Five - seven is currently in service with military and police forces in over 40 nations , including Canada , France , Greece , India , Poland , Spain , and the United States . In the United States , the Five - seven is in use with numerous law enforcement agencies , including the U . S . Secret Service . In the years since the pistol ' s introduction to the civilian market in the United States , it has also become increasingly popular with civilian shooters . History . Development . The Five - seven pistol and its 5 . 7×28mm ammunition were developed by FN Herstal in response to NATO requests for a replacement for the 9×19mm Parabellum cartridge and associated pistols and submachine guns . NATO called for two types of weapons chambered for a new cartridge — one a shoulder - fired weapon , and the other a handheld weapon . According to NATO , these new weapons , termed personal defense weapon s ( PDWs ) , were to provide " personal protection in last - resort situations when the user is directly endangered by the enemy [ . . . ] . " In 1989 , NATO published document " D / 296 " , outlining a number of preliminary specifications for these weapons : FN Herstal was the first small arms manufacturer to respond to NATO ' s requirement ; FN started by developing a shoulder - fired personal defense weapon , the FN P90 , along with a small caliber , high velocity 5 . 7×28mm cartridge type . The original 5 . 7×28mm cartridge , called the " SS90 " , went into production with the P90 in 1990 . This cartridge type was discontinued in 1993 , and replaced with the 5 . 7×28mm " SS190 " , which used a heavier and slightly shorter projectile weighing 2 . 0 g ( 31 grains ) . The reduced length of the SS190 projectile allowed it to be used more conveniently in the Five - seven , which was under development at that time . In 1993 , Jean - Louis Gathoye of FN filed a United States patent application for a delayed blowback operating system intended for the Five - seven pistol , and " U . S . Patent 5 , 347 , 912 " ( " Elements for decelerating the recoil of the moving parts of a fire arm " ) was received the following year . In 1995 , FN officially announced development of the Five - seven pistol , and a prototype of the pistol was publicly displayed the following year . With some improvements , a double - action only model of the pistol went into production in 1998 , and a single - action model called the " Five - seven Tactical " was then introduced shortly afterward . The Five - seven first entered service in May 2000 , when the Cypriot National Guard ( Greek : " Εθνική Φρουρά " ) purchased 250 pistols for their special forces group . 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 FN 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 . 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 ; the Five - seven pistol is currently in service with military and police forces in over 40 nations throughout the world . Present . Historically , sales of the Five - seven pistol were restricted by FN to military and law enforcement customers , but in 2004 the new " Five - seven IOM " model was introduced and offered to civilian shooters for use with 5 . 7×28mm sporting ammunition . The IOM model incorporated several modifications to the weapon ' s design , such as the addition of an M1913 accessory rail , a magazine safety mechanism , and fully adjustable sights . Although offered only with sporting ammunition , the Five - seven ' s introduction to civilian shooters was met with strong opposition from gun control organizations such as the Brady Campaign . Further development of the Five - seven pistol led to the introduction of the " Five - seven USG " model , which was approved by the ATF as a sporting firearm in 2004 . The USG model incorporates a conventionally shaped square trigger guard , a reversible magazine release , and other minor changes . In 2013 , the " Five - seven MK2 " model was introduced , replacing the USG model . The MK2 model has cocking serrations on the front of the slide , all black controls , and slightly different iron sights . Design . The Five - seven is a semi - automatic delayed blowback pistol chambered for FN ' s 5 . 7×28mm ammunition . The pistol appears hammerless , but it has a concealed hammer . Polymer materials are used extensively in the pistol ' s design , and even the steel slide is encased in a polymer shell . In addition to providing reduced weight and greater resistance to corrosion , this also prevents unwanted light reflection . The slide ' s polymer shell gives the pistol the appearance of being constructed entirely of polymers , but the slide interior , barrel , trigger , springs , pins , and similar parts are all steel . However , the pistol is unusually lightweight , weighing only 744 g ( 1 . 6 lb ) with a loaded 20 - round magazine . The Five - seven is a full - size pistol , having an overall length of , a height of , and a max width of . It has the same grip angle as the distinguished Browning Hi - Power and M1911 pistols . Despite the considerable length of the pistol ' s 5 . 7×28mm ammunition , the grip is not particularly unwieldy — the distance from the trigger to the back of the grip measures , which is identical to a U . S . Military issue M9 pistol chambered in 9×19mm Parabellum . The Five - seven barrel is cold hammer - forged and chrome - lined , with a total length of and a rifled length of . The barrel has eight rifling grooves with a right - hand twist rate of 1 : 231 mm ( 1 : 9 . 1 in ) , and it weighs . It has a stated service life of 20 , 000 rounds and the Five - seven is noted for being very accurate . Current models of the Five - seven are single - action , having a short and light trigger pull of 2 to 3 daN ( 4 . 4 to 6 . 6 lb " " ) . They have a Picatinny rail for mounting accessories , and a magazine safety mechanism that prevents the pistol from firing without a magazine inserted . The grip texture on current pistols is extensively checkered for a superior hold , and each side of the slide has a series of narrow ridges at the rear to aid grasping . The trigger and trigger guard surfaces also have grooves to reduce finger slip , and the trigger guard is elongated to ease firing while wearing gloves . The Five - seven is currently offered in two different frame finishes ( standard black or flat dark earth ) , and two different iron sight systems ( adjustable sights or low profile fixed sights ) . Ammunition . Particularly significant to the design of the Five - seven pistol is the small caliber , high velocity bottlenecked cartridge it uses . The 5 . 7×28mm cartridge was created by FN Herstal in response to NATO requests for a replacement for the 9×19mm Parabellum cartridge , which is commonly used in pistols and submachine guns . The 5 . 7×28mm cartridge weighs 6 . 0 g ( 93 grains ) — roughly half as much as a typical 9×19mm 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 , 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 for the standard 5 . 7×28mm cartridge type , the " SS190 " , 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 Five - seven , the 5 . 7×28mm SS190 has a muzzle velocity of roughly 650 m / s ( 2 , 130 ft / s ) and is capable of penetrating the CRISAT vest at a range of , or 48 layers of Kevlar material ( roughly equivalent to two stacked Level II Kevlar vest panels ) at a range of . It is also capable of penetrating a PASGT vest at a range of or a PASGT helmet at a range of . FN states an effective range of and a maximum range of for the 5 . 7×28mm cartridge when fired from the Five - seven pistol . In testing conducted by Passaic County , New Jersey Sheriff ' s Department , the 5 . 7×28mm SS190 penetrated to a depth of in bare ballistic gelatin , and a depth of in gelatin protected with a Kevlar vest . 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 , whereas a conventional pistol bullet such as the 9×19mm retains significant energy beyond . 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 pistol are considered suitable for military use under the Hague Convention of 1899 , which prohibits the use of expanding bullets in warfare . Feeding . The Five - seven pistol feeds from detachable box magazines , but it is unconventional in that it feeds cartridges into the chamber without the use of a barrel feed ramp , having a beveled chamber only — the pistol ' s feeding is inherently reliable because of its use of bottlenecked cartridges . The pistol is supplied with 20 - round magazines as standard , or 10 - round magazines for jurisdictions where magazines are restricted by law to a maximum capacity of 10 rounds . The Five - seven will also accept an aftermarket extended 30 - round magazine , which protrudes an additional from the base of the pistol . With an additional cartridge in the chamber , the Five - seven pistol has a total capacity of 11 , 21 , or 31 rounds depending on what magazine type is used . Magazine pouches for the Five - seven magazine are available from various manufacturers . The Five - seven ' s magazine can be disassembled for cleaning or lubrication by removing the polymer floorplate . The magazine body is constructed of polymer , with steel inserts at the feed lips . Unlike a conventional pistol magazine , it feeds from dual feed lips , with a follower that has the same appearance as that of an M16 rifle ' s magazine , and which is loaded in the same manner : by pushing cartridges straight down into the magazine , rather than pushing them down and back . This setup makes it very easy to load individual cartridges into the magazine . The magazine floorplate has a slight finger spur , and four holes in the left side of the magazine body allow a convenient estimate of the amount of remaining ammunition . Controls . All controls ( excluding the trigger ) on the Five - seven USG and earlier models are grey polymer , in contrast to the black polymer frame and slide cover . Similarly , all of the controls on the Five - seven FDE and Five - seven ODG models are black polymer , in contrast to the flat dark earth and olive drab polymer frames . A takedown lever is located at the front on the left side of the weapon ' s frame , and a slide release is located at the rear on the left side of the frame ; these controls are protected from accidental movements by slight projections in the frame contour . A chamber indicator , in the form of a pin inside a tiny hole , is provided on the left side of the slide . When a round has been chambered , this pin will protrude , which is sufficient to provide both visible and tactile indication of the chamber ' s status . Current models of the Five - seven have an ambidextrous manual safety device , which is located in an unconventional position : one control is found on each side of the frame above the trigger guard , where it is reachable with the trigger finger or support hand thumb . A red dot is visible here when the safety is deactivated and the pistol is ready to fire ; when the safety is moved to the raised position , it is activated and the red dot is no longer visible . The Five - seven ' s push - button magazine release , located on the left side of the frame where the trigger guard intersects with the grip , is square - shaped and reversible for left - handed shooters . The Five - seven can be disassembled quickly and easily , by using the left hand to retract and hold the slide rearwards , while simultaneously using the left - hand thumb to push and hold the takedown lever rearwards . When the slide is released , it moves forward freely and the complete slide assembly can be disengaged from the frame , whereupon the barrel ( and captured recoil spring ) can be removed from the slide . This level of disassembly is sufficient to perform thorough cleaning of the pistol , and FNH USA recommends no further disassembly except by an authorized armorer , FN Herstal , or FNH USA . Reassembly of the pistol is done in the reverse order , except no use of the disassembly lever is necessary . Sights and accessories . The Five - seven has a sight radius of ; the pistol is currently offered with either adjustable sights or fixed sights . The " three - dot " type adjustable sights consist of a 2 . 9 - mm ( 0 . 12 in ) square notch rear and a 3 . 6 - mm ( 0 . 14 in ) blade front , which has a height of . The sights are targeted at , but can be adjusted for either windage or elevation . The " three - dot " type C - More fixed sights , which are offered as a low profile alternative to the adjustable sights , can only be adjusted for windage . The fixed sights are targeted at using SS195LF ammunition , and are available with or without tritium - illuminated inserts ( " night sights " ) to aid use of the pistol in dim lighting . The Five - seven is supplied with a lockable hard case , a locking device and keys , a magazine release reversal tool , a sight adjustment tool ( not included with the fixed sights model ) , a cleaning kit , an owner ' s manual , and three 20 - round magazines ( or three 10 - round magazines , where restricted by law ) . The Five - seven can be used in conjunction with a wide range of firearm accessories ; holsters are offered by various manufacturers , and the pistol ' s MIL - STD - 1913 ( " Picatinny " ) accessory rail will accept tactical light s or laser aiming devices . With the use of an extended , threaded barrel , the pistol can also be fitted with various sound suppressors developed by Advanced Armament Corporation , Gemtech , Silencerco , and other manufacturers . The Gemtech " SFN - 57 " , which was developed in 1998 specifically for use with the Five - seven , is a matte black aluminum suppressor with a length of , a diameter of , and a weight of . Israeli manufacturer FAB Defense offers a complete PDW conversion kit for the Five - seven , designated the " KPOS G2 FN 5 . 7 " , that allows the pistol to be reconfigured into a shoulder - fired personal defense weapon , and CornerShot offers a weapon system compatible with the Five - seven that allows the shooter to aim and fire around corners without being exposed . Controversy . The Five - seven pistol and 5 . 7×28mm ammunition were originally restricted by FN to military and law enforcement customers , but in 2004 the new " Five - seven IOM " model was introduced , and offered to civilian shooters for use with 5 . 7×28mm 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 controversy in the United States after the Brady Campaign stated that commercially available 5 . 7×28mm 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 a smuggled Five - seven pistol can sell for up to 66 , 000 peso s ( US $ 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 controversy in the United States , following the 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 people 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 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 . Users . The first military organization to adopt the Five - seven was the Cypriot National Guard ( Greek : " Εθνική Φρουρά " ) , which purchased 250 pistols in May 2000 for its special forces group . By 2009 , the Five - seven was in service with military and police forces in over 40 nations throughout the world . In 2009 , the Military of Libya purchased 367 Five - seven pistols from FN Herstal , along with various other FN weapons , in a controversial sale valued at 11 . 5 million euros ( US $ 15 . 8 million ) . In 2011 , these weapons were used by Muammar Gaddafi ' s military forces in the 2011 Libyan civil war , and Libyan rebel forces were also photographed using captured examples in the war . In the United States , the Five - seven is currently used by over 300 law enforcement agencies , including the U . S . Secret Service . Military and law enforcement organizations using the Five - seven include :