what is the proper dove tail measurement for

[rjohns94]

the rear sight on a winchester 1894 (circa 1903) I thought 3/8 but it really does not measure out as such. Source of such? thanks.

[J Miller]

Mike,

When you say it doesn't measure out as such, is the slot too big, or too small? Every Win 1894 and 94 I've ever had used the 3/8" dovetail for the rear sight. Even my early 1900s SRC.

Joe

[Gun Smith]

The standard for dovetail sights in the U.S. has been 3/8" since at least the 1860's. The clones from Europe, South America and the rest of the world are metric. I don't have the metric dimension at hand. I have no experience with the Japanese Brownings, so I'm not sure about them.

[Sixgun]

Mike, The other boys are right. Every Winchester erer made has 3/8" dovetails for the front sight and the barrel sight.

Hey! You going to the Lebanon show tomorrow? I'm going to peddle a pair of 99% Savage '99's in .308 I'm tired of looking at. I should be there by 8.-------------Sixgun

[Griff]

Mike, The other boys are right. Every Winchester erer made has 3/8" dovetails for the front sight and the barrel sight.

Hey! You going to the Lebanon show tomorrow? I'm going to peddle a pair of 99% Savage '99's in .308 I'm tired of looking at. I should be there by 8.-------------Sixgun

Jack,
Check yer PMs.
Mike, 3/8". Or more precisely, .375 across the bottom of the dovetail. If your sight is loose, take a point punch and "dimple" the surface of the sides on the sight. This should raise the sides enough that they can grip the dovetail.

[rjohns94]

the outside edge of the base of the dove tail measured .368, not .375. I will pick one up in 3/8" (which I knew it was suppose to be) tomorrow and I will see how that goes, thanks.

Sixgun, nope not going to the show. Wish I could have hooked up with you, I want to offload a BLR in .308 too.

[Sixgun]

the outside edge of the base of the dove tail measured .368, not .375. I will pick one up in 3/8" (which I knew it was suppose to be) tomorrow and I will see how that goes, thanks.

Mike, The cuts can be off by 10 thou or more, especially if other people pounded sights in and out. If the sight is loose in the dovetail, you can do what griff said or you can just epoxy it in. I must have done that 500 times

[Nate Kiowa Jones]

the outside edge of the base of the dove tail measured .368, not .375. I will pick one up in 3/8" (which I knew it was suppose to be) tomorrow and I will see how that goes, thanks.

Mike, The cuts can be off by 10 thou or more, especially if other people pounded sights in and out. If the sight is loose in the dovetail, you can do what griff said or you can just epoxy it in. I must have done that 500 times

Hi Mike,
As Sixgun said they can be off and it will depend on just how well the sights were initially fitted. It all depends on how the base was installed. The sights should be installed from the right side driven in to the left and of course they should be removed in reverse. I've had people tell me that dovetails are cut into the barrel on a taper. That's just not how they do them. Standard dovetails or at least the most common are 3/8 (.375-.380) X 60 degree straight across cut. The taper that these folks are seeing is the results of driving the sights in and as they go in they swedge the dovetail out on the right side and the bases down on the left side creating this taper. That's why it's important to always install from the right and remove from the left.

For years until about 2000 Rossi did an odd ball size rear. Those were around .400. I suspect it was because they had a 55 gallon barrel of off size new rear sights and rather than ditch those they made oversize cutters to accommodate them. The current Rossi's have standard 3/8X60 degree cuts but they still don't spend a lot of time fitting the sights. They just hammer the new sights in and this swedges those dovetails out. As Griff said you now need to grow some metal. Stippling the bottom of the sight works, but you can also push the tops of the dovetail down with a flat face punch. The new sight will cover these marks. Worst case you may need to shim under the new sight. Whatever you do resist the urge to stipple the bottom of the dovetail if it's a big bore like a 44 or 45 cal. If you get carried away you can damage the bore.
On a side note, I've seen Rossi's that had tight spots in the bore because Rossi forced the poorly fitted sights in.

[Cliff]

My take on it. Just file on the sight base which is .375 so it will fit into the barrel slot, which you say is .368. It isn't much. Easier to replace the sight than it is the barrel metal. Use a sharp, "safe" file with fine cut only cuts on one or two sides. Cut a little, try it, if not try a bit more. Should be firm or tight fit. At least that is the way it worked for me. Good Luck.