Installing Trijicon SRO on a Glock 45 MOS

Here’s a quick guide on how to install a Trijicon SRO on a GLOCK 45 MOS. You could follow this same guide for any GLOCK MOS model, and would work well for the RMR as well.

I follow the GLOCK recommended procedure, with a few tweaks, and different screws (stronger!).

GEAR – what you’ll need…

GLOCK 45 Pistol, unloaded and field stripped.
Trijicon SRO
MOS Adapter Plate # 2
Screw driver with both T10 Torx and T15 Torx bits.
For adapter plate – QTY 2 – M3 x 6mm (o.5 mm x 6 mm) Torx plus flat head screw. Highly recommend McMaster-Carr, and they describe them as Black-Oxide Alloy Steel Torx Flat Head Screws, M3 x 0.50 mm Thread Size, 6 mm Long. Tensile strength of 140,000 psi.
For SRO – QTY 2 – 6/32 x 3/8 Torx plus flat head screw. Same source – head to McMaster-Carr. Tensile strength of 140,000 psi.
Loctite blue / non-permanent.
CLP Lubricant / Cleaner

On screws – I opt to get a hold of the strongest fastener I can – hence the McMaster-Carr sourced Torx screws with 140,000 psi tensile strength.

I’m not sure what the supplied screws are, but it’s easy to get the strongest alternative available. Same with the screws that come with an SRO – not sure of the specs.

That being said – I’ve run the supplied screws from GLOCK on a stock adapter plate (different gun) for 10,000+ rounds with no issue. Same with screws from Trijicon. So you do you… McMaster-Carr is 10 minutes away, so I go there!

STEP 0 – Clear & check, and field strip the GLOCK pistol.

As always, gun safety is the number one priority. Clear the pistol by unloading, checking, and disassembling it into the lower receiver, slide, barrel, and spring.

Only work with the slide for this install, and never keep live ammo in the work area. The basics.

It’s handy to work on top of a paper towel – easier to see the screws, and helps with any oil or Loctite spills.

You could put the slide with some soft grippers in a vise – which I do when I install iron sights. For optics install, the bench is easier for me.

STEP 1 – Remove Cover Plate

Use the T10 Torx bit to remove the retaining screws in the cover plate that GLOCK installs on all the MOS versions. Counter-clockwise… 😂

You can / should retain the cover plate and screws for the future if you ever remove the optic, as GLOCK recommends you only shoot the pistol with the cover plate installed, or with an optic.

Do not use the cover plate screws to install the adapter plate or optic!

STEP 2 – Clean and Prep the Surface, Adapter Plate, Screws

Clean both the area below the cover plate, as well as the adapter plate using CLP. Both areas get a light coat of lubricant before install.

I also lightly lubricate the underside of the SRO before installing to help with moisture – especially on an EDC gun.

Prep the screws by applying a small dab of Loctite for better holding power. I use the blue / removable version.

Loctite, a slow moving polymer, helps keep the screw in place under stress, and won’t let it back out.

STEP 3 – Install the GLOCK adapter plate

Use the T10 Torx bit to install the M3 screws for the adapter plate.

Don’t over tighten. Hand tight is more the plenty. Just like a car tire change, check each screw against the other.

WARNING! Adapter Plate Rant…

On adapter plates – I’ve seen a lot of hype about how the stock adapter plates (from GLOCK) are no good, and how there are “better” aftermarket plates available. Often from shooters who’ve never even used the stock plates…🤦‍♂️

And I thought so too… until I used one from the company that starts with CH… which promptly broke mid-stage in a USPSA match. Not fun!

Their design, while good, turned out to be too weak. And, I used their V3, and now they’re on a v4… 🤷‍♂️

When I wrote to them about a replacement, all I got was a 10% coupon off for the newest version.

That gun (a GLOCK 34) got a stock adapter plate installed, as did my carry gun (a GLOCK 19 MOS). No more after-market junk… No more instagram shooters with Gucci setups.

And, don’t talk to me about gaps between the SRO and the slide, how thick the stock adapter plates are, yada yada, or the need to get your slide custom milled…

You’re working on a $500 gun. Why on earth would you mill the slide for $200, and have to re-coat it with something that isn’t nDLC?

If you have evidence of where the GLOCK stock plates don’t work or have broken, I’d love to see it… And no, your over-torqued screws don’t count! 😂

Same goes for screws – the screws that were supplied with the adapter plate from CH… didn’t fit! I say that again – the supplied screws DID NOT FIT THEIR OWN adapter plate. Rant over!

STEP 4 – Install the SRO