Fixing a Glock; Slide Lock Spring
An overview with pictures

One day at the range this Glock 23 stopped working. Right away we knew what happened, the slide lock spring had broken and the slide lock no longer would stay up in position. The shooter who owns this Glock keeps a log book so he knew this failure happened at approximately the 14,000 round point. Once we took a look inside to replace the spring, we saw that this Glock was old enough to be using the older narrow Slide Lock Spring (as seen on the right). The newer Glock Slide Lock Spring is wider so it should last much longer. We will still probably start to replace these springs at around the 10,000 round count to be on the safe side however.

The Glock 23 Slide Lock Spring snapped right at the bend in a narrow area of the part

Glock 23 older narrow Slide Lock Spring (as seen on the right) and newer Glock Slide Lock Spring which is wider