the 22 mag is alil taller alowing the 2 extra rounds but will work in a 23, but not vise versa. some of the mag will hang out of the grip though

another dumb fact: if you decide you want to try out a 357sig, all you have to do is drop in a 31 or 32 barrel in you glock (depending on what model you have) and go to town. cuz the 357s work in the 40cal mags

The G22 magazine has a slightly sharper angle between the floorplate and the mag body, to match the difference in the base of the frame cuts between the G22 and G23. If you press the bottom of a G22 frame against a tabletop, the barrel and slide are parallel to the tabletop; if you do the same with a G23, the barrel and slide will point at a slight upward angle.

Otherwise (as said above), the G23 mag should hold (and have counter holes on the back of the mag body for) 13 rounds of ammunition. The G22 mag holds 15.