View Full Version : Changing out rear sight on S&W revolver

Big Don
September 20, 2007, 12:17 AM
I managed to break off one side of the rear sight on my Model 66 and I want to replace it myself. I have the new sight but am a bit perplexed with the arrangement for getting one out and one in. Anyone have some suggestions for someone who is not a mechanical genius but does have a good supply of smithy tools and usually follows directions pretty well? ;)

September 20, 2007, 09:41 AM
If you are replacing just the blade, you will need a new windage screw and nut. The existing one needs to be broken/twisted off, to remove the old blade.

The screw is available from S&W, Brownells, Midway, etc...

Good Luck...


September 20, 2007, 06:13 PM
The entire rear sight or just the sight blade?

To remove the entire sight, turn the elevation screw to raise the rear sight, and take some of the strain off. DO NOT back the screw all the war out.

Remove the screw at the front of the leaf and slide the entire sight backward and off the frame.

When reinstalling the sight, you have to fit the tiny square nut on the bottom into the "T" slot on the frame.

To change out the sight blade:
For tools, you'll need a GOOD, FITTED gunsmith's screwdriver bit. You can buy the right bit from Brownell's.
The right bit is #210-3. Stock number 080-210-330.
DO NOT try to use a S&W rear sight screwdriver since it's not strong enough, or any type of standard screwdriver.

You'll need a staking punch. This can be a center punch with a rounded-off point, or even a nail, and a bench block to use as an anvil. You can simply put some magazine cover paper or shim stock on a vise anvil.

You'll need either a S&W rear sight spanner "wrench" or a pair of jeweler's tweezers.

Buy a rear sight blade kit from Brownell's or S&W.
Sight blades are sold for different barrel lengths of the gun.
You MUST buy the correct blade kit, since these come in different heights for different guns.
Longer barrels take a different height then the same model with a short barrel.
There are also plain black or white outline blades.

The sight kits comes complete with the blade, a new windage screw, and a new windage screw nut.

Here's the actual process of changing out the rear sight blade:

Turn the windage screw COUNTERCLOCKWISE until it stops turning.
Get the screwdriver well seated in the windage screw slot, then forcibly turn it farther until it shears.
The S&W sight windage screw has a weakened area on the shaft to allow the screw to shear.
(NOTE: As a alternative method, use a small drill to drill off the flared windage screw staking in the windage nut.)

Hold the sight over a table and gently bump it until the windage screw head moves out of the sight base just enough that it can be pulled the rest of the way out.
BE CAREFUL, under the windage screw head is a TINY spring and plunger, don't loose them.

Push the windage screw and blade over to the side until you can grip the shaft of the screw and unscrew it from the blade.

Use solvent to degrease and clean the sight base. Dry, then apply a good lube to all parts.

Screw the new windage screw into the new blade.
Slip the tiny windage screw spring and plunger into place in the base, then insert the new windage screw and blade into the base, making sure the spring and plunger are in the right position.

Press the windage screw into the base until it's seated in the base, with the spring and plunger under it.
Hold everything in place until the nut is installed.

Press and hold the windage screw firmly into the base.
Screw the tiny windage screw nut onto the windage screw shaft until it snugs up against the sight base.
BACK IT OFF 1/4 of a turn.

(Use a S&W spanner tool or tweezers to snug the nut down against the base, then back it off).

Place the windage screw head on a brass bench block, then use a punch to gently flair the hollow end of the windage screw shaft down into the nut.
Be careful to keep the nut from turning while riveting the windage screw.
(For a punch use a center punch with the point rounded off, or even a nail with a re-shaped and rounded point)

All that's needed is a good flair on the end of the screw shaft to lock the nut in place.
This doesn't take a lot of hammering.

Test the windage screw to insure the sight has a full range of windage adjustment, and doesn't bind.

Big Don
September 24, 2007, 12:56 AM
Dfariswheel, many thanks for an excellent primer on changing the sight blade! Based on what you've given me, I may just find myself a good smithy! On the other hand, I love a good challenge so I may just contact Brownell's, get the parts/tools and give it a try. ;)
JoeHatley, thank you for your response too. Just one of the many benefits of TFL.

James K
September 24, 2007, 06:39 PM
Dfariswheel, that is an excellent post on changing the S&W sight blade. I hope folks save it.

It sounds very complicated (and is) but I bet you can do it in a lot less time than it took to write up the procedure.


September 25, 2007, 06:41 PM
It's not as bad a job as it sounds.

If you take the trouble to get the right tools, and do it once, it becomes fairly fast and easy.

James K
September 26, 2007, 01:21 PM
I have probably done several dozen of those sight changes. When S&W first came out with the white outline sight, everybody and his brother-in-law just had to have one, so there was a real run on them. As you say, once you have done a couple, it is pretty easy.

I also used to take the original black sight and cut two holes for white dots. At first I removed the sight, then got so I could do the job with the sight on the gun.


September 26, 2007, 06:26 PM
Getting the holes spotted EXACTLY right is what's tough.

They have to be in exactly the right place or the gun will shoot to one zero when the dots are used, and another when the sights are used.

What I started doing was to convert them to the "Von Stavenhagen" type rear sight.
That's a white bar directly under the sight notch with a white dot in the front.

For the front, I'd replace the red insert with a black insert, then drill a shallow oval-shaped hole in the insert.
Fill the hole with Gloss White paint, and from the rear it looks like a round white dot.
Line up the white dot with the white bar, and you're on.
This has no effect on targeting as long as you get the front dot positioned right:

James K
September 26, 2007, 07:47 PM
Yep, getting the holes right is the hard job. A good example of "measure twice (or a dozen times) cut once."

That front sight is a very nice job. I never did one like that.