[cazbass]

After following the thread called "Sight Installation - Lubricant / Loctite / Nothing", it got me wondering if there's an actual consensus of which surface to lightly file down on a rear sight's dovetail. After installing a dozen or so sets of sights into various Glocks (with a sight pushing tool), once or twice the fit was SO TIGHT that I had to bear down on the lateral force needed to fully insert the sight.
I want to emphasize, I know sights shouldn't be filed unless absolutely necessary for fitting purposes. They should be somewhat tight, or else they won't stay!
But which surface should be filed down? The bottom surface? Or the front (or rear) of the dovetail?

 

[Silver-Bolt]

I have had to file a few. Which surface depends on the sight. I will align the sight with the dovetail on the slide to determine which surface to file. It varies sight to sight. Sometimes it might be a single surface and sometimes all three.

 

[Filthyphil]

I've done 5 or 6 guns now. One was really tight. You can muscle it in

 

[cazbass]

I have had to file a few. Which surface depends on the sight. I will align the sight with the dovetail on the slide to determine which surface to file. It varies sight to sight. Sometimes it might be a single surface and sometimes all three.

That's interesting... if you have to file a rear, it seems reasonable (to me) to start with the bottom, and go from there.

I've done 5 or 6 guns now. One was really tight. You can muscle it in

That's what I've done... just muscle it in. It's just that on one of my guns, the rear sight was so tight I ended up regretting not filing it. I'm thinking the trick might be to make my judgement whether to file or not, by how soon it physically stops when nudging it in with finger pressure.

 

[Introvert]

A dealer broke my rear sight recently. The Night Fision brand specifically states that they have to be fitted and would require shaving.

It also stated to only install via the vise grip and tap method.

I only paid $30 to have mine fitted.

 

[Filthyphil]

A dealer broke my rear sight recently. The Night Fision brand specifically states that they have to be fitted and would require shaving.

It also stated to only install via the vise grip and tap method.

I only paid $30 to have mine fitted.

Oh THAT mist be the one I had to force in.
I got another one coming now too

 

[SJ 40]

Installing Fixed Rear Sights with Dave Dawson

This man knows more about sights than anyone I'm aware of, watch and learn.

 

[santareg]

I have used Steel City Arsenal sights on 7 different slides (I use the mid height size with optics). All have been tight, I used a diamond stone and work the bottom and sometimes, if needed, the dovetail "V" notch a little with a tri-file. I work them down slowly until they go in half way in then a drop of CLR and use a sight pusher to press them in the remainder of the way. I install the locking set screw just to fill that hole since they are tight and really don't need it.

Optical illusion (right photo above) - frame lifted Nomad slide higher then Glock slide

 

[cliffspot]

The bottom. If you file the front or back you change the sights angles...that's a no go! Set the sight on a file and go slow. As you take some off the bottom, you reduce the front to back measurement. No oil or loctite! Only use loctite if it has a set screw....and use BLUE! Not orange or red!

 

[GlockGuide]

Most of my experience is that removal of some of the finish is all that’s needed. I follow Dawson’s video for fit and filling. If I need to file, I file where the marks on the sight show (sides).

Only once have I had a sight that the fit was so bad I needed to remove some metal and that was years ago. I used to run into a lot of sights that needed a touch with the file to properly fit, now I’m not real sure where my file is. Maybe Glock or the sight makers have become more consistent?

 

[cazbass]

The bottom. If you file the front or back you change the sights angles...that's a no go! Set the sight on a file and go slow. As you take some off the bottom, you reduce the front to back measurement. No oil or loctite! Only use loctite if it has a set screw....and use BLUE! Not orange or red!

cliffspot, I think your comment nailed it for me. I've always been pretty mechanically-minded, but for some reason the question of which surface to address, for an overly-tight rear sight, has eluded me. But now, with a little thought and focus, and your comment, it's so clear to me I can't believe I didn't grasp such an elementary concept! In the case of a tight-fitting rear sight, a slight reduction of the bottom surface will have the effect of relieving the stress between the floor of the slide's dovetail and the angled sides of the slide's dovetail. Dang. So simple. Thanks!

Most of my experience is that removal of some of the finish is all that’s needed. I follow Dawson’s video for fit and filling. If I need to file, I file where the marks on the sight show (sides).
Only once have I had a sight that the fit was so bad I needed to remove some metal and that was years ago. I used to run into a lot of sights that needed a touch with the file to properly fit, now I’m not real sure where my file is. Maybe Glock or the sight makers have become more consistent?

I agree, Dawson's video is a good one.

 

[SJ 40]

cliffspot, I think your comment nailed it for me. I've always been pretty mechanically-minded, but for some reason the question of which surface to address, for an overly-tight rear sight, has eluded me. But now, with a little thought and focus, and your comment, it's so clear to me I can't believe I didn't grasp such an elementary concept! In the case of a tight-fitting rear sight, a slight reduction of the bottom surface will have the effect of relieving the stress between the floor of the slide's dovetail and the angled sides of the slide's dovetail. Dang. So simple. Thanks!

I agree, Dawson's video is a good one.

"In the case of a tight-fitting rear sight, a slight reduction of the bottom surface will have the effect of relieving the stress between the floor of the slide's dovetail and the angled sides of the slide's dovetail. Dang. So simple. Thanks!"

Dave Dawson covers that in all his videos, always the first place to address and the the dovetail angles if needed. If done properly can be installed with hammer and punch no need for a pusher to possibly bend sight or void manufactures warranty.

 

[cazbass]

"In the case of a tight-fitting rear sight, a slight reduction of the bottom surface will have the effect of relieving the stress between the floor of the slide's dovetail and the angled sides of the slide's dovetail. Dang. So simple. Thanks!"

Dave Dawson covers that in all his videos, always the first place to address and the the dovetail angles if needed. If done properly can be installed with hammer and punch no need for a pusher to possibly bend sight or void manufactures warranty.

Yep on all counts. One small question - it seems to me that one of the skills needed to be a "master rear sight installer" (if there is such a thing) is to be able to judge if you're going to have to reduce the bottom sight surface before actually pushing it in (whether by hammer/punch or a pusher). In other words, beginning the push on the rear sight with your finger - and seeing how far in it goes before binding. I guess sheer experience will eventually tell you that, but it seems to me there should be a rough guide-mark. Half-way would be too loose... maybe one-third of the way would be ideal...??? Hope I'm making sense.

 

[SJ 40]

You are correct,I first push the sight in by finger and see how far it will go. like to shoot for not quite half way and then file or hone the base and recheck and I don't care how many time I have to repeat to get it right.
It doesn't happen often that a sight will be too lose but the old trick for that is to with a prick punch the bottom of the dovetail slot in the base/bottom of the base of the dovetail in the slide.

 

[cazbass]

You are correct,I first push the sight in by finger and see how far it will go. like to shoot for not quite half way and then file or hone the base and recheck and I don't care how many time I have to repeat to get it right.
It doesn't happen often that a sight will be too lose but the old trick for that is to with a prick punch the bottom of the dovetail slot in the base/bottom of the base of the dovetail in the slide.

Ah okay. Makes perfect sense. Thank you!

 

[Filthyphil]

I just did a night fision on my gen5 17
It was brutal
If you have a wooden post you can brace the tools handle against it and use the slide as a handle and crank that ***** on

 

[JLD]

I just did a night fision on my gen5 17
It was brutal
If you have a wooden post you can brace the tools handle against it and use the slide as a handle and crank that * on

I got 2 pairs of night fisions. One for my G19 and G43x and the sights were extremely hard to fit even with a sight pusher. And I ended up try’s to file the front and rear parts of the sight and not the bottom of the sight and I managed to get them in but even they took a lot of force almost enough to where I almost stopped. And now that I know to start with the bottom of the sights might have to order some more to actually install them better and take the thought of my slide dovetail breaking on my Glocks.

 

[mc1911]

After following the thread called "Sight Installation - Lubricant / Loctite / Nothing", it got me wondering if there's an actual consensus of which surface to lightly file down on a rear sight's dovetail. After installing a dozen or so sets of sights into various Glocks (with a sight pushing tool), once or twice the fit was SO TIGHT that I had to bear down on the lateral force needed to fully insert the sight.
I want to emphasize, I know sights shouldn't be filed unless absolutely necessary for fitting purposes. They should be somewhat tight, or else they won't stay!
But which surface should be filed down? The bottom surface? Or the front (or rear) of the dovetail?

I only file the bottom of the sight, not the dovetail on a normal installation.