Trapdoor 1877 Sight Slider Slides

[Riqrob]

My TD has the 1877 rear sights that have the smooth slope as opposed to the notched slope. Anyway, it slides with each shot when not in the lowest position. Sure messes up 200 yard shooting! Is there an easy fix without changing sights? Would like to keep it as is. Thanks in advance.
Rick

[Scharfschuetze]

Rigrob,

I'm not familiar with an 1877 sight. the 1873 model sight was replaced in 1879 and 1873 Springfields with the 79 sight, low arch breech block and short wrist stock are generally reffered to as 1873s with the 1879 modifications. As I recall, there were actually two or three versions of the 1879 sight although in general aperance they looked pretty much the same.

Can you post a photo of yours?

[Larry Gibson]

My TD has the 1877 rear sights that have the smooth slope as opposed to the notched slope. Anyway, it slides with each shot when not in the lowest position. Sure messes up 200 yard shooting! Is there an easy fix without changing sights? Would like to keep it as is. Thanks in advance.Rick

That was one of the problems with the M1877 sight that led to the improved M1879 rear sight.

If yours is an original M1877 rear sight the problem is (quoting from The 1st real manual for marksmanship made by and for the Army; A Course Of Instruction In Rifle Firing by COL. T. T. S. Laidley issued by the Ordnance Department, U.S. Army in 1879: "The proper degree of friction is obtained by means of a spring riveted to the slide in rear of the leaf." In other words there should be a spring between the leaf sight and the slide to maintain friction. If the spring is not there it obviously is missing. If it is there it probably is weak from age.

If you have a repo M1877 rear sight (I have not seen or heard of a repo of the M1877, a M1873 yes though as I have one) is there a spring or have the made the leaf as a spring also? On the M1873 repo there is a screw instead of a rivet so some tension may be adjusted with it?

Larry Gibson

BTW; the only real differences between the M1873 and the M1877 rear sights are the ramp (smooth curve, not stepped) and the sight leaf on the M1877.

[Tom Trevor]

One other thing you can also do,BE CAREFUL!. Look at the slider and you will see a spacer inbetween the staff ears with pliers GENTLY pinch the staff after moving the slider to the top and this will give it enough friction to hold it in place.

[montana_charlie]

The sides of the slider bar appear to be thick enough to allow the addition of a small setscrew which would bear against the outside of the staff.