SIG Sauer P220 The SIG Sauer P220 is a semi - automatic pistol made by SIG Sauer . Designed in Switzerland by what was then SIG Arms AG , it is manufactured in Eckernförde , Germany , by subsidiary J . P . Sauer und Sohn GmbH . It uses the Browning linkless cam short recoil action of self - loading with a double - action / single - action ( DA / SA ) trigger mechanism . The P220 was the basis of what is now a large family , including the P225 , P226 , P228 and P229 pistols , which are in service in the armed forces and police of many countries . History . The SIG P220 was developed for the Swiss Army as a replacement for the SIG P210 , which had been developed during World War II ; in service it is known as " Pistole 75 " ( P75 ) . For development of the P220 , SIG collaborated with J . P . Sauer & Sohn of Germany , thus , the P220 and all subsequent pistols from SIG are properly known as SIG Sauer pistols . In 1975 , Switzerland became the first nation to officially adopt the P220 as the " Pistole 75 " ( P75 ) chambered in 9 mm Parabellum . Other nations to adopt it for military use include Japan and Denmark though only to special forces . It was succeeded by the SIG Sauer P226 . Upon completion of their military service , commissioned officers of the Swiss armed forces can obtain ownership of their P220 service pistols by paying an administrative fee of thirty Swiss franc s . Design . The P220 operates by the locked breech short - recoil method pioneered by John Browning . On firing , the slide and barrel are locked together until , after a few millimeters of rearward movement , the barrel is cammed down at the rear after the pressure has dropped enough when the bullet has departed the barrel , whereupon the slide completes the rearward stroke ejecting the spent cartridge . The recoil spring then propels the slide forwards , stripping a round from the magazine , and in the last few millimeters of forward movement , the barrel is cammed upwards at the rear , locking the slide and barrel together again . Instead of the locking lugs and recesses milled into the barrel and slide of other Browning - type weapons as the Colt M1911A1 , Browning Hi - Power and CZ 75 , the P220 variants ( and many other modern pistols ) lock the barrel and slide together using an enlarged breech section on the barrel locking into the ejection port . This simplifies manufacture and has no functional disadvantages . The slide of the P220 series is a heavy - gauge sheet metal stamping with a welded - on nose section incorporating an internal barrel bushing . The welding is so well - executed it is almost impossible to detect . The breech block portion is a machined insert attached to the slide by means of a roll pin visible from either side . The frame is of forged alloy with a hard - anodized coating . While designed for ease of production , the SIG 220 series is of the highest quality and there is no compromise in durability or functionality compared to pistols produced using more traditional methods . The SIG P220 series incorporates a hammer - drop lever to the rear of the trigger on the left side , which first appeared on the Sauer 38H before World War I . After chambering a round , the hammer will be cocked , so for safe carriage the hammer drop is actuated with the thumb , dropping the hammer in a safe manner . The P220 also introduced a firing pin block safety which is activated by the trigger mechanism — similar to the one used in the Colt M1911 ' s Series 80 pistols . The pistol may now be holstered , and can be fired without actuating any other controls . The first shot will be fired in double action mode , unless the firer chooses to manually cock the hammer . Double action trigger pressure is around 12 – 14 pounds , and subsequent shots will be fired in single action mode with a lighter trigger pressure of around 6 pounds . There is no separate safety lever to manipulate ; the hammer drop is the only manual safety device . As with other double action pistols such as the Walther P38 and Beretta 92F , some training is required to minimize the difference caused by the different trigger pressure between the first double action shot and subsequent single action shots when the hammer is cocked by the rearward movement of the slide . Variants . The original SIG P220 had a ' heel - mounted ' magazine release located behind the magazine well , but a design revision on newer SIG P220s moved the magazine release to the left - side of the grip , behind the trigger . The P220 was then later modified again with a redesigned slide , grips , and other minor changes to the frame . Even more recently was the addition of a Picatinny rail to the dustcover as standard . The major difference in slide design , between the older model SIG pistols and the current production , is that the older model slides were stamped whereas the current production models are milled on a CNC machine . The stamped models have an end piece at the muzzle end which is welded in place , to complete the slide . Additionally , the older stamped slides feature a removable breech block . This breech block is pinned to the slide with two hollow roll pins , one pressed inside the other , with their split ends opposed . The newer milled slides are a one piece unit and do not have a removable breech block . The SIG P220 also comes in P220R and P220ST versions . The base and R models have an aluminium alloy frame with a stainless steel slide ( if made by SIG Sauer in the US ; German made versions still use a blued , stamped steel slide ) ; the ST model has a stainless steel frame and slide . The R and ST models also have a Picatinny rail , beneath the slide and barrel , allowing for fitting of accessories such as lights or laser sights . The P220 was initially imported to the United States as the Browning Double Action ( BDA ) and then as the P220 . The P220s sold under the Browning Arms Company marque in the USA c . 1977 – 1980 had the heel - mounted magazine release until Browning discontinued it from its product line in the early 1980s ; the discontinuation from the Browning product lineup was due to its poor sales and its then - ' space age ' appearance ( similar to the AR - 15 / M16 assault rifle ) . These particular P220s ( or Browning BDAs ) will have the stamping scroll which reads ' Browning Arms Company Morgan , Utah and Montreal PQ ' on the left hand side of the slide and ' SIG - Sauer System Made in W . Germany ' on the right - hand side with the serial number scrolled beneath . It was offered for sale in 9 mm , . 38 Super ( a rare model ) , and . 45 ACP . However , all modern P220 variants are only available in . 45 ACP . Until recently , all SIG P220s were DA / SA and featured a de - cocking lever ( and no external safety ) just forward of the slide catch . This has changed with the introduction of DA only , DAK , and SA only models . The DA only and DAK models do not have a de - cocking lever or safety , and the SA only models only feature an M1911 style external safety . SIG has also introduced the SAS ( SIG Anti - Snag ) model — which is dehorned , has no accessory rail , and is designed for concealed carry — and the Elite model , which includes the new short - reset trigger , a beavertail grip , front strap grip checkering , and front slide cocking serrations . P220 Rail . The P220 Rail ( or P220R ) is effectively the same as the P220 , but it has a Picatinny rail on the dustcover . The P220R usually represents the more recently produced P220s , and has now become the standard P220 . P220 Carry . A new P220 with a shortened barrel ( 3 . 9 " ) and slide , but a full - sized frame . It is available in double action / single action ( DA / SA ) , single action only ( SAO ) , and DAK double action variant . All models with the exception of the SAS concealed - carry version come with an accessory rail . P220 Compact . A new P220 variant recently released . It comes in four versions : Blued with beavertail , stainless ( two - tone ) with beavertail , blued with rail ( no beavertail ) and stainless with rail ( no beavertail ) . It features a shortened slide , and a compact frame and has a capacity of 6 + 1 . It is possible to use the 8 round magazines of the P220 Carry which will give it an 8 + 1 capacity . Adapters are available to cover the portion of the magazine which protrudes from the bottom of the grip . It is essentially a replacement for the discontinued P245 , and is meant to address complaints about the P220 Carry ' s full - size frame in a concealed carry pistol . P220 Combat . The two " Combat " models , the P220 Combat and P220 Combat TB ( Threaded Barrel ) , are available in DA / SA only . Their frames are colored " Flat Dark Earth " in compliance with the Combat Pistol program . The Combat model comes with night sights , a Nitron - finished slide and barrel , phosphated internals , and a Picatinny rail . The TB model features an extra 0 . 6 " on the barrel , and external threads to accept a suppressor . The P220 Combat is only chambered in . 45 ACP , and is supplied with one 8 round magazine and one extended 10 round magazine . P220 ST . A version of the SIG P220 handgun made by SIG Sauer with a reversible magazine release , stainless steel slide , and stainless steel frame . Changing to a stainless steel frame from the lighter alloy frame normally used is meant to reduce felt recoil . The ST models are typically bare stainless ( all " silver " ) , though SIG Sauer has produced Nitron finished ( all " black " ) ST versions for police department trial and evaluation ( T & E ) guns . P220 Classic 22 . This model ' s primary purpose is as a practice or range pistol . The Classic 22 model replaces the typical stainless steel centerfire slide assembly with a lighter aluminum rimfire slide chambered in . 22 LR . The Classic 22 also has a different barrel , guide rod , and recoil spring then the larger caliber models . It incorporates the same frame and operation as centerfire P220 models . The Classic 22 model is available as a stand - alone firearm or as a conversion kit to an existing centerfire P220 . Likewise , conversion kits ( the Sig Sauer X - Change Kits ) exist to convert a . 22 LR P220 into . 45 ACP . The conversion can be accomplished by field stripping the firearm and replacing the slide assembly and magazine — a process that can be accomplished in minutes . The Classic 22 use a 10 - round polymer magazine in lieu of the steel magazines used by the centerfire models and conversion kits . The P220 Classic 22 should not be confused with the Sig Sauer Mosquito . 22 LR pistol . The Classic 22 is a full - sized P220 while the Mosquito is modeled on the P226 but is 90 % of the size . Another difference is that the Classic 22 is manufactured by SIG Sauer while the Mosquito is made under license by German Sport Guns GmbH . The size difference means that the Mosquito cannot be converted " up " , and full - size SIG Sauer pistols cannot use the Mosquito ' s slide assembly . P225 / P6 . The SIG P225 is a more compact version of the SIG P220 . The Swiss Army was looking for a new pistol and the SIG P210 was too costly to manufacture . The Swiss Army wanted a cheaper semi - automatic handgun , that would still provide excellent functionality and a double - action trigger . SIG , in cooperation with a German arms company , J . P . Sauer & Sohn , developed a new pistol , the Pist 75 ( as it was known in the Swiss Army service ) . The 9mm SIG - Sauer P220 , debuted with various new and inventive features . It utilized a single column magazine holding eight 9 mm rounds and had a 3 . 9 in . barrel . A new German police standard , in the mid - 1970s , prompted SIG - Sauer , Heckler & Koch , and Walther to develop new pistols that met the standard : the Walther P5 , the SIG - Sauer P225 ( known as the P6 ) and the Heckler & Koch P7 . ( In addition , Mauser had a design that never went into full production . ) Each German state was free to buy whichever pistol it wanted to . Initially , the P220 was submitted ; the P225 / P6 was created to conform with the mid - 1970s West German police requirements for its standard service pistol . The SIG - Sauer P225 was the least expensive ( due mainly to the inventive design ) and received the majority of the orders . To be able to manufacture that many handguns , SIG acquired a controlling interest in J . P . Sauer & Sohn in Eckenförde , Germany to manufacture parts for the P220 . This is also where all P225s were manufactured . The only difference between the P6 and P225 — the P225 ( which was adopted by US civilian law enforcement ) has a lighter trigger pull , whereas the P6 ' s trigger pull is heavier . The P225 has tritium fixed sights ; P6s had fixed sights only . Genuine P225s manufactured for the West German Police will have a " P6 " stamp on the right side of the slide . A new police standard was adopted in Germany in 1995 , and the P225 is in the process of being replaced . German police pistols can be identified by the hammer , which has small " ear " or " hook " . According to section 7 . 7 of the German manual , the cutout is the " Deformationssporn " , which means “ deformation spur ” . This was a requirement of the West German Police for all their pistols , regardless of manufacturer , to alert police armorers if the pistol was dropped on its hammer . Many of these surplus German police pistols have been imported into the U . S . recently . Because of its compact size , the P225 / P6 is quite readily usable for concealed carry . In U . S . states where high - capacity magazines were prohibited , the P6 / P225 was usually in high demand . P245 . The SIG P245 variant is chambered only in . 45 ACP ( hence the name ) and was developed primarily for the US market as a civilian ' s concealed sidearm , or as a police backup weapon . The SIG P245 has a reversible magazine release giving the user the choice of operating it with their left or right thumb . It normally takes 6 round magazines , but can also accept the 7 , 8 , or 10 round magazines designed for the P220 . A grip extender is available for use with these longer magazines . One of the major differences in construction between the P245 and the P220 Compact is that the P245 was only built using the older stamped steel slide design with a removable breech block . The P245 is no longer manufactured by SIG , having been replaced by the P220 Carry and , more recently , the P220 Compact .