Loose rear sight

[Crawfish]

Full disclosure: I am not new to BP shooting, but have not been active for many years.
Once upon a time, I built a percussion Ky pistol from a kit. It ended up pretty nice, and was surprisingly accurate. It is still in excellent condition, except for one thing.
The rear sight can be easily moved in the rear dovetail. Not good.
How could I anchor this thing? My thought was a very thin piece of brass shim under the sight so it was tight enough to keep it anchored.
However, there may be a better way. Anyone have a solution?

I want to take this old soldier out and shoot it, but the sight is a problem.

 

[jethro224]

There are 3 ways that I can think of right off hand.
One is the one you mentioned. Shim the sight. I don't like this idea.
Another way is to lightly peen down the very edges of the dovetails VERY carefully.
The third, and probably the best, is to take the sight out and pen the edges of the base to thicken them and tighten them in the dovetail.

 

[azmntman]

Jethro right, I wouldn't shim, lots easier to lightly whack

 

[EC121]

You could also fit another sight and not deform the dovetail too much. One thing not to do is to try to punch the bottom of the dovetail to raise metal. I have seen that deform the bore.

 

[necchi]

One thing not to do is to try to punch the bottom of the dovetail to raise metal. I have seen that deform the bore.

Well that actually works if a person is careful and peens small divots to raise some metal.
Any idiot can beat the snot out of a barrel with a punch and mall and deform it without even needing a dovetail as a target.
Take the beer out of the Gorillas hand and keep him away from guns.

 

[BrownBear]

I'll add a 4th, one I often resort to.

Take the sight out and barely open your vise jaws, just enough for you to flip the sight and let the blade to slip down into the gap in the vise jaws- exposing the bottom of the sight base while also supporting it. Now use a sharp punch to dimple that bottom surface in a few spots, raising the metal around the dimples in the process.

When you go to slide the sight back into the dovetail those little raised areas nicely fill and tighten the gap. No filing and reshaping the sides of the base.

I most certainly would NOT do any peening on the barrel dovetail.

 

[necchi]

Dove tail sights are often "peened" in to a semi permanent position with one small divot in each corner.

 

[Arcturus]

As was stated by Brown Bear, any peening should be done to the sight, NOT the barrel.

 

[jethro224]

I'll add a 4th, one I often resort to...

Yep, that would work too.

No filing and reshaping the sides of the base.

If you peen the edges, do the front and rear edges, no filing and reshaping of the sides is needed that way either. It doesn't take much at all and you gotta be careful.

I most certainly would NOT do any peening on the barrel dovetail.

Not in the bottom. But the very edges of the lips works well if done VERY carefully. I've done it to a couple where the lips had been stretched by too aggressive sight installation.

 

[garra]

What may be a less intrusive fix is to pull the sight and put solder on a spot on the bottom of the sight. Tap back into the dovetail base.

 

[Rifleman1776]

As was stated by Brown Bear, any peening should be done to the sight, NOT the barrel.

:applause: Yes. Gorillas cannot reason things like that. :wink: Plus, it is temporary. Hard to put back steel on the barrel. Don't like the sight? Toss and replace.

 

[BrownBear]

...pull the sight and put solder on a spot on the bottom of the sight. Tap back into the dovetail base.

That's a goodun, too.

A little dab'll do ya. :wink:

 

[Billnpatti]

Many years ago I had the exact same problem with a sweet Pedersoli .32 caliber rifle. I changed the sight but the new sight was just a tad too small for the dovetail and it wasn't tight enough to stay in a set position. I took it out and shimmed it with a piece of aluminum from a Coke can. I made the piece of aluminum small enough that it didn't show unless you looked closely at the sight. If I remember correctly, I had to do a bit of adjustment on the thickness of the shim with some sandpaper but the aluminum being soft was not hard to sand down for a nice snug fit. It worked like a charm and never came out or worked loose.

 

[crockett]

Well, I'm going to be different from everyone else and suggest a paper shim. Cut it oversize lengthwise so that it sticks out after the sight is tapped in place. Then trim off excess paper. SEE IF THAT WORKS. If it does, fast and easy fix. If you are not happy with the paper shim then use a center punch and dimple the underside of the sight.

 

[BrownBear]

One thing about that paper shim. In my experience it will teach more than you want to know about rust. It collects water while you're cleaning, while you're hunting in the rain, while you're lost on foggy days, and while you're sweating on humid days. Then holds it nice and tight to the metal where you can't get at it.

 

[hawkeye2]

You can drill a few holes in the base of the sight, not all the away through, and fill them with solder. After you have sighted the gun warm the sight till the solder flows. That will lock the sight in place and it will still be movable/removable by heating.

 

[BrownBear]

Ohhhhh...

I like that!

Thanks.

 

[Artificer]

A LOT of good ideas mentioned so far and :hatsoff: to those who mentioned them.

One problem one may run into is as you look at the sides of the dovetail on the barrel, the angled sides at the top may not match the front and rear angled sides of the sight that well, especially if the sight was not machined to the same angle as the dovetail. You may not be able to find a replacement sight that makes up for that.

So in that case you are almost forced to peen down the front and rear tops of the dovetail cut on the barrel. I have found the best way to do that is with a hard/polished piece of steel or hammer head that is laid on each edge and then struck by a lead or copper mallet. This peins/peens down the edge smoothly and all across the edge at the same time - so you don't wind up with what looks like scales from peening. It also closes the open gap/s at the top of the dovetail. The nice thing about using a hard/polished piece laid on the edges is that it often or even usually does not disturb the finish much or at all.

Gus

 

[nhmoose]

You could also fit another sight and not deform the dovetail too much. One thing not to do is to try to punch the bottom of the dovetail to raise metal. I have seen that deform the bore.

Peen the edges duh! Not over the bore standard real gunsmith does it that way

 

[jethro224]

So in that case you are almost forced to peen down the front and rear tops of the dovetail cut on the barrel. I have found the best way to do that is with a hard/polished piece of steel or hammer head that is laid on each edge and then struck by a lead or copper mallet. This peins/peens down the edge smoothly and all across the edge at the same time - so you don't wind up with what looks like scales from peening. It also closes the open gap/s at the top of the dovetail. The nice thing about using a hard/polished piece laid on the edges is that it often or even usually does not disturb the finish much or at all.

That's exactly how I have done it. Works like a charm.

I like the solder ideas too. Learn something new all the time on here. :thumbsup: