Glock 42 Description Once you start with perfection – you stay with perfection. The G42 is the ideal pistol to start or enhance your shooting experience. The innovative design of the hybrid steel-polymer slide chambered in our first .22 caliber round provides lightweight and low recoil functionality for optimal control. The G42 was thoroughly tested with a wide variety of ammunition to ensure maximum performance and redefine what small can do. The G42 is a compact size pistol with the ability to adapt to nearly every hand size by using the different back straps supplied with the pistol.