Tang sight hole spacing M1894 & 64

[Irascible]

Does anyone have a factory drilled and tapped, for tang sight, M1894 (or 64) Winchester that they could measure and let me have the hole spacing and thread size? Or tell me where to look it up. Thanks

[NickSS]

I just bought the tang sight and the rear hole is the existing tang screw. The sight comes with a longer tang screw. The front screw is a 10-32 and has to be drilled and tapped. I did this by installing the sight and location the center of the hole and center punching it. I then drilled it and ran a 10-32 tap in and the sight is still on my rifle.

[405]

The tang sight base holes/screws should be 2 3/16" center to center with the main stock bolt screw being one of them.

[Trailblazer]

The Marbles tang sight comes with two screws. A 10-32 and a 10-36. I believe the original Winchester screw size was the 10-36. When I drilled my 94 for the tang sight I used the 10-32 because that is what is in my tap set and that is probably why Marbles includes that screw size.

[405]

Irascible,
Since you mention M1894 and M64 I assume you mean older, pre-64 Winchesters?

To avoid confusion. Most new tang sights come with 2 screws. Older, used sights may or may not have the correct screws with them. The longer screw is for the stock bolt to replace the one on the gun since it has to be a little longer and a slightly different head to account for the sight base thickness and different countersink. The other is a short screw and is for the front to replace the plug screw that is already in the tang.... most 94s, 64s of that vintage should have the front hole already drilled and tapped with the plug screw installed.

The longer, stock bolt screw should be a 12-28. The front, shorter screw should be a 3/16-36.

Caution, I have seen new production, after market screws sold as replacements for the older Winchesters not be of the correct diameter and/or pitch.

Also, if the two holes in the tang are not exactly 2 3/16" apart center to center then that front screw is not factory done. And if the sight you have doesn't have that same hole spacing it is not for the Win 94/64 original hole spacing.

[Irascible]

Thank you 405. Just what I was looking for. I have an un-drilled/un-tapped M 64 and I wanted to drill and tap as if the factory did it. Until I find an original sight, I am installing a new designed Marbles with the changeable post. One of the holes in the new Marbles is elongated and I figured I would drill and tap it at the factory distance and thread.
Isn't 3/16 a #10 or #12 screw?

[405]

I may be wrong but I think a 3/16 screw diameter is between #6 and #7 size.
No matter, when you do it just double check... 3/16 is .1875

Always good to ask or find out about factory hole spacings. I know Win went to great lengths to avoid drilling and tapping thru any receiver or barrel markings or stamps.
The 2 3/16 hole spacing avoids those marks on the tang.

[Trailblazer]

OK, I went and pulled the plug screw from my 1939 vintage Model 64 that appears to have been drilled and tapped at the factory for a tang sight. The plug screw is .186" in diameter and has 36 TPI. This, gentleman, is a 10-36.

[405]

Trailblazer, you be correct! Glanced at the wrong chart... a sheet gauge chart! :roll:

[Irascible]

Thanks again to 405 and Trailblazer.
"Irascible Curmudgeon"

[detox]

JFYI

On my Winchester Model 94 (1986 vintage) I drilled and tapped my front tang hole @ 2.185" (2 3/16") from center of rear tang bolt hole. This is old factory spacing and will allow many tang sights to fit.