The Glock 23 is a Glock 19 modified to fire the .40 S&W ammunition. It uses a modified slide, frame, .40 S&W barrel and magazine, but is otherwise virtually identical in appearance to the Glock 19. In fact, the two pistols are exactly identical in their external dimensions apart from weight (the Glock 23 is slightly heavier than the Glock 19). Its standard magazine capacity is 13 rounds (However, the standard 15 round Glock 22 magazines can be used). Both G19 and G23 use the same 18 lb. recoil spring, which made many Glock enthusiasts proclaim that the gun was "undersprung", making 20 lb. and 22 lb. springs a popular after-market accessory. The Glock 23 has undergone three major revisions since its introduction in 1990 along with the slightly larger Glock 22. Current models are called 3rd generation Glock 23s.
The Glock 22 and Glock 23 models were the first Glock pistols to be chambered in the .40 S&W cartridge. Both models are highly popular with US law enforcement agencies as well as self-defense shooters. While many law enforcement agencies carry full-size Glock 22s, their detectives, higher ranking officers (Chiefs, Assistant Chiefs, etc.), and supporting personnel often carry the slightly smaller Glock 23. The G23 is capable of utilizing magazines from the G22 models. It is also more easily concealable than the Glock 22.
The Glock 23C is a compensated version, which features a ported barrel and slide to allow some of the gases to escape when the gun is fired. This reduces recoil felt by the shooter and allows faster follow-up shots to be made.
The Glock 23 is available, like all Glock pistols, in a black finish - and a recently introduced olive drab polymer finish. The slide of the pistol remains black on both models.