1903 Model 1 Rear Sight Problem

[maj75]

My 1919 mfg Springfield has the factory sights, plus a Lyman 48 sight. Obviously, the Lyman is the one to use. However, I was looking at the ladder sight and when I tried to adjust it, the windage part does not seem to work. The knob will turn a couple of turns, but then stops. The sight does not move at all when the windage knob is turned. I can tap the sight and get it to move a little, side to side, but not enough to remove it.

I don't want to force anything without knowing what it should be doing. I've read that the windage knob should move the sight and that it is pretty sensitive. If mine is messed up, bad threads or something, is it possible to remove and replace the windage knob?

Help appreciated. I've searched and haven't found the answer.

Thanks.

[Kurt]

I would soak the windage screw with some Kroil for a day. Then, with light pressure against the sight, turn the screw. It should swing all the way and you can remove it and inspect the threads and associated parts.
Sometimes the sight gets crud and dried grease in it and freezes up from lack of use. The knob will turn a little taking up the slack and spring tension but no more.

Good luck.
Kurt

[John Beard]

The rear sight is removed by turning the windage knob counterclockwise until the rear sight disengages from the threads. Then grasp the sight with your fingers and rotate it a little further counterclockwise, then lift it from the barrel.

Your description indicates that your rear sight is binding. In that case, you might have to "help" the windage knob by forcibly rotating the rear sight counterclockwise as you turn the windage knob counterclockwise.

Once you remove the rear sight, you can remove the windage screw by pressing the knob towards the left to disengage the shank from its recess on the left side. Then slide the screw out of the base with a twisting motion.

Hope this helps. Good Luck! And Happy Holidays!

J.B.

[maj75]

I looked at the windage knob and compared it to reference photos. My windage knob is missing the collar on the side with the adjusting wheel.

I've turned the knob and I can get a few turns but then it binds up. I've tapped the rear sight while turning the knob but I can't get any more movement on the knob. I haven't tried pliers on the knob for fear of screwing it up.

I don't know where the collar went. It wasn't on the gun when I got it. I'll try soaking it with penetrating oil and get a little more forceful with the knob.

[John Beard]

You are correct. The windage knob has a small spring-loaded collar behind the knob. If the collar is missing, then your windage knob is defective and should be replaced. You, therefore, should have no reservation about taking whatever reasonable measures are necessary to remove it.

The missing collar is puzzling. The collar is permanently installed and does not come off. The fact that it's missing suggests that the windage screw/knob was damaged at one time and was re-assembled without the collar. And that may be related to the binding you're experiencing.

The windage screw has a reduced diameter in the center. The screw, therefore, cannot be removed until after the sight has been removed as described in my previous posting.

Permit me to add a word of precaution. Turn the knob counterclockwise as far as you can get it, and use pliers as necessary. But as you apply more force to the knob with pliers, you may strip out the knob on the shaft. If that happens, remove the knob, then tap the screw out from right to left. But first be sure that you've turned it counterclockwise as far as it can go.

Hope this helps. Good Luck! And Happy Holidays!

J.B.

[Fred]

Is the spring missing too?

[maj75]

I do not feel a spring. I can't push the wind age knob in or pull it out.

I will use more force and if the windage knob breaks, I should be able to extract remains without damaging the leaf part of the sight.

Thanks!

[Fred]

Have you a photo of what's going on?

[Parashooter]

It isn't easy to tune up a stiff, worn, or sloppy '03 rear sight but it can be done if you have a light touch and go slowly.

Let's start with a picture of the components:



The repeatability of the windage adjustment depends on a good fit of the stud (a) in the hole (A), a good sliding fit between the rear lip (b) and the rear radius (B), full engagement of the windage worm threads (c) with the windage gear sector (C), and the tension of the worm spring (d).

The objective in tuning the sight is to eliminate play and binding. First step is to tighten up the stud/hole fit. If you have a machine shop you can fit a bushing after opening up the hole with an end mill, perfectly indexed. If not, peening the top of the stud until it binds, then lapping with fine compound (600 grit) will work for a while. Any play here is multiplied nearly four times at the leaf end of the movable base and, like a bad wheel bearing, no amount of tweaking the other parts will fix it.

Once the stud is a good fit in the hole, put the sight together without the worm screw assembly and tighten up the lip-radius fit (b-B) by tapping the lip in toward the radius with a soft brass or copper hammer at x-x. Test for binding by swiveling the movable base from side to side between taps. When it starts to bind, apply some compound and lap it smooth. Repeat the tapping and lapping until there is full contact throughout the normal range of movement, no slop and no binding. If needed, do the same for the front lip (e) which, when properly fitted, acts as a spring to exert a gentle down-pressure on the movable base and prevent it from rocking.

Clean off the abrasive, stone any burrs on the opposing conical surfaces of the worm assembly and its seat, make sure the worm spring (d) is not weak or collapsed (if it is, get a new worm assembly - they're cheap). Lube everything that makes contact with moly or graphite grease. Assemble the sight and center it.

Try to wiggle the movable assembly left and right with very little force to observe any slop. The last few thousandths of side play are sometimes impossible to remove without a new worm. Don't worry about them. If there is more than that, try peening the stud again.

Now push the movable base hard to the right against the tension of the worm spring. It should return itself to the original position without binding. If not, take it apart and lap some more. Be sure to clean out all the lapping compound.

Any tapping and peening has to be done very gently with a light, smooth hammer. The steel of the sight components is soft and deforms easily. Most components except the fixed base are widely available. If your '03 is in completely original condition, don't peen the stud - use the bushing in the hole on a spare movable assembly and keep the original assembly safe and unaltered.

[Kurt]

If the sight in question is impossible to move, the lip "e" may be jammed down or the rear "x" may be jammed in. I can't see a windage screw keeping the ladder from moving to that degree.

Kurt