Navy Rear Sight Oddity
 

I have noticed that some Navy sights have a straight groove cut forward from the small oval well in front of the "V" area. I have attached pictures of two of these.

Anyone have any idea why some of the Navy sights have this and others do not?

Thanks,
Lukehttp://boards.rennlist.com/upload/Na...ightGroove.jpg

I have added a picture of a 1916 sight without the groove in front of the "V" and a 1917 sight with the groove.

Any theories?http://boards.rennlist.com/upload/19...RearSights.jpg

Luke, the Navy toggle that I just aquired has the mill cut past the dished out part. I can only speculate that these were probably cut by hand and the operator simply either didn't cut deep enough or cut all the others too deep?

My GUESS would be that it is some kind of manufacturing sight index mark that was used during some manufacturing procedure during sight alignment...

But that is pure speculation from a manufacturing engineering standpoint... no documents to back it up.

Luke, for what's it's worth, my 1917 Navy does NOT have the index mark!! [img]smile.gif[/img]

Luke,
two of my four model 1914's have that mark. None of my 1906's and my 1908 have it. I recently posted a navy rear toggle note and pictures under "value of a navy toggle" and that toggle has the groove.
Big Norm

Just a theory, but the groove may have been intended to either reduce glare from the flat surface or - and this is more probable - it was supposed to improve the sight picture.

While we are guessing, I might as well go off the deep end too! Since there seems to be some variation (with and without the groove) within the same model type/year, could it be that each sight was individually registered to point of aim at 100 meters, so that some V-notches would be cut more or less deep than others to adjust the strike of the bullet? My 1906 does not have the groove. I also noticed, and it might be an illusion because of the camera angle, but it appears that the "web" of the sight where the notch is cut is varies in thickness, i.e. Luke's 1916 appears thicker than the 1917. My 1906 has the thick web. This could suggest that the Navy rear sight may have been produced by more than one source, with final assembly and regulation performed by DWM. How's that for a flight of fancy?! <img src="graemlins/c.gif" border="0" alt="[ouch]" /> http://boards.rennlist.com/upload/Web.jpg

Ron,

The 1917 is my restored Navy Shooter.
It has been refinished at least twice. When I found the gun, it had already been severely buffed and salt blued. Most of the sharp edges had been rounded by the hard buffing, probably to remove the pitting so common to Navy Lugers.

That's the way I bought it, and I gave it to Ted Green to restore. He accepted the challenge and did a great job, but he did not add any metal.

I think that the earlier buffing could possibly have produced the thinner area you mention.

The theory that DWM might have had 2 suppliers of this part seems like a reasonable possibility.

Ronny,
how do you get those neat red lines in there?

But now that I played a small role in this discussion, I am going to throw a clinker in here. While looking at my sights, I noticed that there were many navy sights of all years that do not have machine marks in that tiny area. Indeed, many seemed to have been made with an ECDM (Electro Chemical Discharge Machine). These machine will sometimes leave bumpy surfaces of varying degrees. But given the machining of the time, I know that is not possible. Ok big guys, lets hear some theories on that one.
Ok, I take all this back. What I did was look at a navy that was restored. The restorer probably used an acid bath to remove the old bluing. The other gun was just dirty. After cleaning I saw the machining marks. Sorry about that!

Big Norm <img src="graemlins/icon501.gif" border="0" alt="[icon501]" />

The sight groove was manufactured on manual equipment and was dependent upon the machinist cranking the knob or handle to retract and approach the metal to be machined. The slower machinist would retract further from the cut to allow more time in a fast, repetitious, mindless operation. The faster, more conscientious worker would retract only far enough to clear the workpiece.
(I have supervised thousands of such workers.)

Ron, if you look closely at the two pictures of the sights, you'll see that they are not at the same scale. The upper sight is much larger (closer picture) than the lower and would thus appear to have a thicker web. Even so, there is a difference in the two sights. I just don't believe it's as large a difference as the pictures seem to indicate.

Big Norm: I copy the picture and paste it into PowerPoint, add the lines, group the photo and lines, copy and paste into PaintShop Pro as a new image, resize as necessary, save as a .jpg file and post it on the forum.

Doubs: I noticed that they were not the same scale, but as you also observed, it looks like a difference in thickness even considering the scale.

I looked at an early '06 Navy with the extra cut, and a 1917 that does not have the cut. There is a noticeable difference in the depth the V cut when comparing the pistols side by side. With just a small machinists square for a scale, the difference appears to be around 1/32 deeper on the sight with the extra cut. I have never read if the sights were actually regulated, or if this is just within manufacturing tolerances.

Johnny,
With all of the tight tolerences of the remainder of the gun, it is a bit difficult for me to envision careless machining as being the source of the variation in the V cuts. Think I will stick with my wild idea about regulation, particularly since I had never thought of it before. It is so seldom that I have an original thought I'd like to enjoy it for a while!
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