Rear sight construction?

[Jerry V Lape]

I want to build a rear sight with two blades.  The first will be fixed and the second one pivoted to be rotated up when needed.  This all looks straight forward enough until I start thinking about how the front blade is to be locked into position (both in the up position and when folded out of the way).  None of the photos of such sights reveal how the second blade is secured.  Is the foot of the blade eccentric with a small flat spring to act against or how is it done?

[D. Taylor Sapergia]

Hi Jerry,

I've build a couple and the last one was for my Kuntz rifle.  Here's a picture of the original which is the fancy lady in the MET, and a picture of the one I made.



Now, I had no way to examine the retaining spring, so I used the info from "The Modern Gunsmith" by Howe.  Basically, there is a very shallow dovetail lengthwise on the bottom of the base.  A thin flat spring is set into the dovetail, and an essentric cam on the bottom of the sight leaf snaps the sight back against the verticle wall, or down firmly against the base.  Note that I had to cut a relief in the bottom of the sight's dovetail in the barrel for the spring as it is depressed and the leaf rolls over centre.

This is an interesting and rewarding project.

[T*O*F]

Just out of curiousity, why go thru all the trouble when you can just make it L shaped so the short sight is normal and the taller one flipped up?  Personally, I wouldn't add leaves unless two or more were required as in express sights.

[Dphariss]

The one I made holds from friction.

Dan

[eldeguello]

 Is the foot of the blade eccentric with a small flat spring to act against or how is it done?

Many are made this way, and it is certaionly a very effective way of doing it!  However, I have a "2-blade" (one standing, one folding) rear on my Jaeger, and it has a folding leaf that is held standing pretty much by the friction with which the blade is fitted into the recess on the sight base.  It would be  much more satisfactory if it had a leaf spring bearing on the base of the blade when standing...

[D. Taylor Sapergia]

My filing is not fine enough to have friction alone keep the leaf vertical.  The spring makes the leaf snap to attention, ensuring it is exactly the same each time.  Incidentally, I have no idea where the ball hits with the sight up...never had to shoot that far, yet. 
but I was emulating an original, and it was a fun thing to do.  I used to use such a sight on my Jaegar, too, and with it I won several long range round ball offhand matches, so they do have their place.  Gold nuggets were the prizes.