How to Disassemble a Glock. It takes about 30 minutes and is not difficult, but it does require some patience and attention to detail. A lot of people have trouble with trigger group removal because they don’t use the right tools. If you follow these instructions, though, you should be able to do it without any problems!
Step 1: Remove the magazine by pulling it out of the grip with your thumb and forefinger
Step 2: Pull down on the slide lock lever located above the trigger guard and hold it while simultaneously pushing down on both sides of the gun frame (See Picture). The slide should now be unlocked from its position in front of the barrel. Be careful not to lose track of this lever as we continue to disassemble because once we finish, you’ll need to use this same motion again before reassembling for safe firing.
Steps to remove the slide:
a) Push forward on the front of the top and rear hips at the same time. This will create a gap between these parts. We want this space in order to be able to grip both sides of the frame with our thumbs (See Picture).
b) Now, push down using your thumbs on the rear hips in order to release them from their place. You will feel a pop as they come free (See Picture).
c) With both thumbs, now grip each side of the frame and pull straight up with enough force so that you are able to remove the slide from its resting position atop the lower part of your gun frame.