A modified Glock 19, the Glock 23 is enabled to fire the .40 S&W ammunition. G23 uses a modified frame, slide, magazine and .40 S&W barrel, but is otherwise practically identical in appearance and appeal to the Glock 19.
The two pistols are exactly identical in their physical external dimensions aside from the weight of the pistols (the Glock 19 is slightly lighter than the Glock 23). The standard magazine capacity of the Glock 23 is 13 rounds (Despite that, the standard 15 round Glock 22 magazines can be used). Both G23 and G19 use the same 18 lb. recoil spring, making 20 lb. and 22 lb. springs a very popular after-market accessory for the weapon. The numerous similiarites between the two exceptional designs includes that the Glock 23 can easily and effectively be converted to a Glock 19 by replacing the barrel with a "conversion" barrel, and using Glock 19 standard magazines.
The Glock 23 has been through three major revisions since its primary introduction in 1990 along with the slightly larger Glock 22. Present market models are called 3rd generation Glock 23s.