On my last range trip I had a disturbingly high number of premature slide locks (1-3 per magazine). At first I thought maybe it was me, since I have had issues with premature slide locks on Glocks due to my grip before but thought I had it sorted out. Stripped the handgun for cleaning afterwards and noticed very little downward tension on the slide catch and I couldn't see the tip of the slide catch spring that usually extends past the locking block pin back towards the magazine well. Detail stripped the gun and sure enough, the spring had broken. Sad day. At least the replacement part is cheap and I had one handy. Only 3,124 rounds through the gun since issued.
Broken slide stop on the top, new one on the bottom.