Rear Sight Cutout Question

[Rick H.]

I have a 3rd Generation 3904 that has the factory adjustable rear sight on it. I want to do something a little different for a rear sight, but I need to know what the dovetail angle of the rear sight cutout is. If anyone has an idea what this angle is, or where I can find out that what it is please let me know. Thanks in advance....

Rick H.

 

[Alk8944]

The standard dovetail angle on US made forearms is 60 degrees, regardless of the width of the dovetail.

 

[StakeOut]

The 5904 shipped with the rabbit ear type adjustable rear sight and one that was in a dovetail cutout in the slide.

Millett made replacement sights for both types that came as a set with a front blade or rear alone.

They are designed to fit all 400,500 and 600 series S&W Autos

They occassionally can be found on ebay.

The attached photo has the dovetail type on the right and the rabbit ear replacement type set(with front blade) on the left

EDIT:the dovetail sight is removed by placing the slide in a vice with plastic jaw covers and using a brass punch and a hammer tapping the sight out from left to right only.It may take a lot of heavy tapping to remove the present sight.

 

[Rick H.]

Thanks for the replies gents. I have the old rabbit ears sight out and that wasn't a problem although I was surprised by how tight the sight base was in the dovetail. I want to make a filler plate for the sight cutout on the slide, but I am not sure what the dovetail cutout angle is that S&W used. It's obviously greater than the typical 60 or 65 degree dovetail. I thought someone may have an idea what dove tail angle Smith cut on these. It appears via my angle plate gauges that it's about 80 degrees but I am not sure as I can't get my gauge located exactly right.

Rick

PS to Stakeout: Could you give me the package information on the sight in your picture on the left? That would be the replacement Millett sight for the S&W rabbit ear adjustable sight. I'll have to watch for one of those for sure.

 

[BMCM]

S&W had to be different and went with 74° dovetails. I had a helluva time hunting down a dovetail cutter to make some stuff for one of my guns. I eventually came across a Chinese vendor selling on fleabay and bought one of his 75° cutters that got the job done. Brownells also carries a small 74° x .250 cutter. I was adapting some standard 1911 sights to fit S&W's version of the Novak cut.

Cheers
Bill

 

[Rick H.]

Thanks Bill for the information. I guess you just verified what I discovered today. I stopped in at a well known barrel manufacturer and asked one of the guys I know if he could measure the angle of the sight cutout on the slide for me. He said sure and off he went. He returned a few minutes later and told me the forward and rearward angles were 8 degrees for a total of 74 degrees. So you were absolutely correct on your measurements/calculations. If you don't mind my asking, how did you determine the angle? My friend at the shop used some sort of fancy optical comparator. Thanks for the help to everyone!!

Rick

 

[BMCM]

If you don't mind my asking, how did you determine the angle? My friend at the shop used some sort of fancy optical comparator. Thanks for the help to everyone!!

Rick

You're quite welcome Rick.
I measure those angles with a Starrett precision protractor and a 10x jeweler's loupe.

Cheers
Bill

 

[03Fatboy]

I may have one (for sale) of the Millet sights on the left if interested I'll check my parts box.

 

[Rick H.]

For those of you that may be interested in the angles involved in the slide cutout for a 3rd Gen adjustable rear sight here is the printout from a angle comparator from my slide.

Rick H.

 

[Gunhacker]

You're quite welcome Rick.
I measure those angles with a Starrett precision protractor and a 10x jeweler's loupe.

Cheers
Bill

What??

With those those Superman like machining skills that you've been wowing us with, in your various project postings over the years... I'm surprised you didn't use your laser x-ray vision to determine it...