Assembly of a Glock Slide

How to assemble a Glock slide:

While it might seem intimidating, its actually quite easy to assemble a Glock slide and after you’ve done it a couple times you’ll be able to do it in a matter of minutes.

There are 8 main steps to assembling a Glock Slide

  1. Install the Channel liner
  2. Build the firing pin assembly
  3. Insert Safety Plunger and spring assembly
  4. Insert Firing Pin assembly into the slide
  5. Insert the Extractor
  6. Install Extractor Depressor Plunger
  7. Install Slide Cover Plate
  8. Insert Barrel
  9. Install Guide rod / Recoil Spring

In this tutorial we will be assembling a Glock 19 Gen 3 aftermarket slide using an aftermarket upper parts kit. The assembly steps for completing a Glock slide are the same for all of their models, but the parts kit will be different for each model.

The Glock 19 (G19), Glock 17 (G17), and Glock 26 (G26) 9mm slides all share the same major components, but have a different guide rod to accommodate the different barrel lengths.

The 40 Cal / 357 equivalents G23 , G22, G27, G35 have the same major components but include a different extractor for the change in caliber

The Glock 21(G21 45 Cal) and Glock 20 (G20 10mm) share most of the same components with the other model Glocks but will each have their own extractor and safety plunger.

Install the Channel Liner

This is a simple step, the channel liner is a small plastic tube that helps to prevent the firing pin spring from binding

note: It may fit tight or loose depending on the tolerance of the liner and the slide cut, it generally will not effect the function. People do leave the channel liner out completely, but that could effect reliability.

Build the firing pin assembly

The firing pin assembly consists of the Firing pin, Firing pin spring, Firing pin spacer sleeve, Spring cups.

  • Insert the Firing pin spacer sleeve over the firing pin and then slide on the firing pin spring

* Trick: A trick we have found, if your kit comes with a channel liner install tool, you can use it to depress the spring and lock it on the firing pin making it easier to install the spring cups ( otherwise this can be the hardest part of the assembly)

  • Pull back on the spring and insert the cups, one at a time works best for us.
  • The completed assembly should look like below:

Insert Safety Plunger and Spring Assembly

Apply a small amount of lubricant to the sides of the plunger hole prior to inserting.

note: make sure the spring stay in the safety plunger while inserting in the hole, it is sometimes easiest to hold the slide upright and insert the spring form the bottom.

Insert Firing Pin Assembly into the Slide

  • Insert the Glock firing pin assembly with the firing pin pointing forward and the striker catch facing the channel in the slide.
  • Press the Safety plunger to allow the Firing pin to lock into place.

Insert the Extractor

The extractor inserts into the side of the slide

Press the safety plunger to allow the Extractor to slip in and lock into place, just like when installing the firing pin.

Install Extractor Depressor Plunger

Insert the plunger with the spring facing the rear of the slide

The plunger should lock down the extractor and you will see the end of it right behind the extractor on the side of the slide.

Install Slide Cover Plate

For the cover plate you will need to use a punch or small flat tipped object

Press the firing pin spacer sleeve down with the punch and slide the cover plate on until it gets close to the Depressor Plunger

Then press the plunger with the same tool and slide the cover plate the rest of the way on. It will click into place.

Insert Barrel

Insert the barrel with the lockup facing down

Install Guide rod / Recoil Spring

Insert the front of the guide rod into the pocket on the front of the slide

Press the spring and slide the guide rod down into place, there are 2 notches, make sure to insert the guide rod down into the bottom notch.

Other assembly and tips:

If the slide hasn’t been assembled before you will also need to install your sights or have a gunsmith install your sights.

if your optic has an RMR and it has been installed or has a cover plate, sometimes the screws can go into the Depressor Plunger tube, you may need to remove the screw to complete install, sometimes you may even need to trim the screw for proper function.

All of our slides have the option to include all the parts for a complete slide assembly. When you purchase a complete slide kit from us we install everything for you. We also sell upper parts kits for Glock slides.

Glock Slides for sale:

Glock Upper parts kits for sale:


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