Ameriglo rear sight drifting after some use

[CarloMNL]

I installed a set of Ameriglo Defoors a few months ago on my 43X and liked them so much I installed a set on my G17.5. Yesterday, I was practicing with the Slimline and was getting nice tight groups that were consistently at 9 o'clock of my aiming point. My presses felt clean but no matter how slowly or quickly I shot, the group was always a few inches to the left of the X-ring. I chalked it up to a bad grip and figured I'd work on that when I got home.

After I cleaned the gun and wiped it down, I noticed that the rear sight had drifted all the way left in its dovetail. I tried pushing on it but the sight wouldn't budge. I went back to the range the following morning to borrow a hammer and punch. It took some forceful taps to sort things out and after a few magazines, I was able to re-establish a zero. I then applied silver Sharpie witness marks to the left and right portions of the dovetail. If the sight moves, I should see some sliver of black and correct things before they get worse.

I know Ameriglo have fans here, as well as contracts with Fed/.gov agencies like the FBI. I've never experienced this drifting before so forgive me if I'm wondering if such is typical of rear sights that do not have set screws.

Is this drifting to be expected? Any tips to mitigate this movement?

[spelingmastir]

Loctite 290 (wicking grade) into the dovetail after confirming zero. How many rounds did it take for your sight to drift?

[CarloMNL]

Loctite 290 (wicking grade) into the dovetail after confirming zero. How many rounds did it take for your sight to drift?

My best guess is about 700 rounds since I installed the sights.

[CarloMNL]

Bit of an update. I emailed Ameriglo to ask for any tips they could share. They offered to send me a replacement set and mentioned that this issue is rare on the 43x/48 guns. Told them I had a spare set in hand and would try that first.

Same issue, but instead of the rear sight drifting left, the new rear sight drifted right after about 100 rounds. Am beginning to think the issue lies with the rear sight dovetail.

Will likely need to go with something that has a set screw on the rear sight.

[HeavyDuty]

I personally don’t understand why more rears don’t have set screws.

[JohnO]

A good number of the rear sights I have installed in Glocks have been oversized. Some removal of material has been required. I would be concerned with a rear sight that has no set screw and fit in relatively easily. Meaning it could be easily tapped in or easily pushed in with a sight pusher. That type of fit would definitely get Loctite.

[ST911]

Is this drifting to be expected? Any tips to mitigate this movement?

Saw variation with some Hacks and I-Dot pros. Peen front edge when loose, muscle or light file passes when tight.

[HTM]

A lot of aftermarket sights like those are very soft steel. A lot softer than the slide. They compress when installed. If you remove them and reinstall on another slide or even they same slide they aren't ever as tight as the first install. Which is why oversized sites that have to be fitted are the best option or ones with set screws. IMO

[Exiledviking]

Loctite 290 (wicking grade) into the dovetail after confirming zero. How many rounds did it take for your sight to drift?This! I learned about this Loctite from Dawson Precision in one of their videos, IIRC. I've used it a few times and it sure appears to do what it's supposed to do.

[BN]

I personally don’t understand why more rears don’t have set screws.

I've drilled and tapped for some rear sights before.

[HTM]

I've drilled and tapped for some rear sights before.

Ones with set screws I never use loctite. I put a very small piece of leather into the set screw hole and tighten. Keeps from biting into the slide and applies sufficient pressure to keep the screw from backing out.

[5pins]

Bit of an update. I emailed Ameriglo to ask for any tips they could share. They offered to send me a replacement set and mentioned that this issue is rare on the 43x/48 guns. Told them I had a spare set in hand and would try that first.

Same issue, but instead of the rear sight drifting left, the new rear sight drifted right after about 100 rounds. Am beginning to think the issue lies with the rear sight dovetail.

Will likely need to go with something that has a set screw on the rear sight.

It's not your pistol, it's the sights. I have seen this problem with a batch of them before. Have Ameriglo replace them.