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After installing a nifty new Marble tang sight on my shooter 62A, I tapped out the rear iron sight and its elevator (from left to right) from the rear barrel dovetail because I’d found a NOS Lyman 12SS blank especially made for small radius barrels.
When introducing the blank into the right side of the dovetail, making ready to tap it in with a nylon tipped punch, to my surprise the blank was a free running fit across the full width of the dovetail with light thumb pressure and never found any interference at all. It would fall out the other (left) side of the dovetail.
My guess is a pilgrim once re-iinstalled the iron sight from left to right, eliminating the taper.
Should I (1) raise several dimples in the base of the dovetail with a prick punch to enable an interference fit? Or (2) supplement the height of the blank with a brass shim to provide the interference? Or (3) paint the botttom of the blank with blue LocTite, slide it in and check for rigidity after it cures?
I know I could buy a new full size blank, which is oversized, and fettle it but the little 12SS blanks are hard to find and look much neater on a rimfire 22 barrel.
- Bill
WACA # 65205; life member, NRA; member, TGCA; member, TSRA; amateur preservationist
"I have seen wicked men and fools, a great many of both, and I believe they both get paid in the end, but the fools first." -- David Balfour, narrator and protagonist of the novel, Kidnapped, by Robert Louis Stevenson.
The way I tighten up dovetails when putting sights in is to tap down the front and back of the dovetail. Normally when you install the sight it will cover the signs of the tapping. The other ways you described will work as well.
Bob
WACA Life Member--- NRA Life Member---- Cody Firearms member since 1991 Researching the Winchester 1873's
Email: [email protected]
November 7, 2015
Offline
I’ll get in trouble for this but my rough duty carry Colt 1911 has a piece of garden variety adhesive tape under the front sight. It’s my edc gun at the moment and I’m very much in the jungle in these trying times. I’ve peened down the upper edges of the dovetail on old Winchesters with good results. If a sight is driven out in the wrong direction or is simply oversize the dovetail won’t grip a standard sight.
Mike
Bill,
I would be inclined to use the Loctite or Super Glue (which can be readily removed with acetone if desired).
Bert
WACA Historian & Board of Director Member #6571L
1873man said
The way I tighten up dovetails when putting sights in is to tap down the front and back of the dovetail. Normally when you install the sight it will cover the signs of the tapping. The other ways you described will work as well.Bob
This is what I’ve seen and done before, like “rolling over” the edges on top down into the dovetail a little…remember small changes at a time.
Zebulon said
My guess is a pilgrim once re-iinstalled the iron sight from left to right, eliminating the taper.
That, or a diff in manufacturing tolerances between Lyman & Win. But even with parts manufactured by Win, manufacturing tolerances can cause fitting problems, such as a Win 98A front sight that I could barely get started in a M 52 brl. Even after filing down the bottom of the sight, I could not drive it all the way into the center position on the brl, & had to compensate with the windage of the rear sight.
I love loose-fitting dovetails because they’re so easy to correct by one of the methods described; it’s the ones that are TOO tight (and there are plenty of them) that I dread encountering.
The issue you would have is if the filler you bought was made wrong and grossly undersize. You don’t want to make it tight and do major modifications.
Bob
WACA Life Member--- NRA Life Member---- Cody Firearms member since 1991 Researching the Winchester 1873's
Email: [email protected]
All good advice. I have no intention of modifying the dovetail mortise on the barrel, except perhaps for raising a few dimples that easily be removed with a flat file. But I don’t think I’ll choose that method first.
My experience with Lyman slot blanks consistently has been they are oversized and need a little tapering. However, this one is from the Fifties, so who knows.
My inclination is to apply a spread of blue Loctite and see if it holds. If it doesn’t fill the gaps when cured, I’ll clean out and try a brass shim.
Clarence, you suggested a single bolt would serve to keep the tang sight base in line and that has proved to be true. As you say. We’re not talking serious recoil here.
I will say this tang sight is very fast to acquire and sharpens the sight picture and depth of field at the same time. The Leupold Compact Rimfire of its day.
- Bill
WACA # 65205; life member, NRA; member, TGCA; member, TSRA; amateur preservationist
"I have seen wicked men and fools, a great many of both, and I believe they both get paid in the end, but the fools first." -- David Balfour, narrator and protagonist of the novel, Kidnapped, by Robert Louis Stevenson.
I use a 1/4″ by 1/4″ shim. It is trial and error to get it placed in the correct position so the sight tightens up where you want it to.
Bert H. said
Bill,I would be inclined to use the Loctite or Super Glue (which can be readily removed with acetone if desired).
Bert
Thanks, Bert. I think we’re going to use a small brass shim and secure th sandwich with Loctite. Belt and suspenders. Bill
- Bill
WACA # 65205; life member, NRA; member, TGCA; member, TSRA; amateur preservationist
"I have seen wicked men and fools, a great many of both, and I believe they both get paid in the end, but the fools first." -- David Balfour, narrator and protagonist of the novel, Kidnapped, by Robert Louis Stevenson.
Chuck said
I use a 1/4″ by 1/4″ shim. It is trial and error to get it placed in the correct position so the sight tightens up where you want it to.
Thanks. Chuck. I’ve just learned two young gunsmiths have opened a shop less than 2 miles away. They’ve gotten sterling reviews for all sorts of general gunsmithing tasks, which encouraged me to give them a try. I needed several small things done to this M62, including the blank install, so I took it by and left it with them this afternoon. They agreed a small shim would be the best solution, with a touch of Loctite to keep the sandwich secure for sure.
They’ve promised the work by Friday. If they do a good job I’ll leave my hybrid Supergrade with them for a chamber cast. They quoted me $70 for a cast, which seems reasonable in today’s dollars.
- Bill
WACA # 65205; life member, NRA; member, TGCA; member, TSRA; amateur preservationist
"I have seen wicked men and fools, a great many of both, and I believe they both get paid in the end, but the fools first." -- David Balfour, narrator and protagonist of the novel, Kidnapped, by Robert Louis Stevenson.
Zebulon said They agreed a small shim would be the best solution, with a touch of Loctite to keep the sandwich secure for sure.
If it requires both, the mismatch in dimensions is extreme! Though I have Brownell’s brass shim stock “kit,” I’ve never used anything but paper shims cut from a business card, unless that’s too thick. And rather than cut the shim to the exact size, I’ve usually cut a long slender one, drove in the sight, then torn or cut off with an Xacto blade whatever overlapped the slot; advantage of paper is that you can blacken the exposed edge with a magic marker. Never had one shoot loose, either.
The blank isn’t loose in the slot so it probably just needs to be elevated a couple of thousandths to grip tightly. You’re right, a thin brass shim is probably enough. I just like the smell of Loctite in the morning.
Clarence, can’t you blacken brass by removing any protective lacquer and letting it oxidize? When I shimmed the Kimber/Brownell bases on my former Model 70 Featherweight, I just rubbed any miniscule visible brass edges with a Birchfield-Casey matte black pen.
- Bill
WACA # 65205; life member, NRA; member, TGCA; member, TSRA; amateur preservationist
"I have seen wicked men and fools, a great many of both, and I believe they both get paid in the end, but the fools first." -- David Balfour, narrator and protagonist of the novel, Kidnapped, by Robert Louis Stevenson.
Zebulon said
The blank isn’t loose in the slot so it probably just needs to be elevated a couple of thousandths to grip tightly. You’re right, a thin brass shim is probably enough. I just like the smell of Loctite in the morning.Clarence, can’t you blacken brass by removing any protective lacquer and letting it oxidize? When I shimmed the Kimber/Brownell bases on my former Model 70 Featherweight, I just rubbed any miniscule visible brass edges with a Birchfield-Casey matte black pen.
No reason to think shim stock has been lacquered. But unless an especially thick shim is needed, I don’t think brass makes a better shim than paper; it’s “slicker” than paper, which for this particular purpose isn’t advantageous, I don’t think.
A thin piece of paper under the front sight as you drive it in works. That’s what I did when I reversed a sight that someone reversed and despite all my careful planning I still managed to drive it in from the wrong side.
I have never had to use loctite. If you use some make sure it is not the permanent stuff. I place the shim in the slot and then drive the blank/sight in. If it doesn’t tighten right where I want it I reposition the shim and try again. The shim does slide as the sight goes in so you have to adjust.
Chuck said The shim does slide as the sight goes in so you have to adjust.
Which is why I cut the shim long enough that it doesn’t matter when it slides; when the sight is centered, tear or cut off what sticks out below the sight base.
Chuck said
I have never had to use loctite. If you use some make sure it is not the permanent stuff.
The various grades (identified by the color) have different temperatures at which the will debond (melt). The Blue Loctite has is near the bottom end of the scale.
Personally, I recommend simple Super Glue. It is readily removed/dissolved with acetone.
WACA Historian & Board of Director Member #6571L
Bert H. said
Chuck said
I have never had to use loctite. If you use some make sure it is not the permanent stuff.
The various grades (identified by the color) have different temperatures at which the will debond (melt). The Blue Loctite has is near the bottom end of the scale.
Personally, I recommend simple Super Glue. It is readily removed/dissolved with acetone.
Loctite is polymethylmethacrylate, a plastic, and can be dissolved with acetone too, as well as lacquer thinner, methyl alcohol, or a hair dryer if you’re patient and more careful than I am. The last time I needed to remove some from the matting on a Model 70 receiver, I used an old toothbrush and some alcohol pads. (Yes, I removed the stock first. Anything that will soften Loctite or Super Glue will play hell with the lacquer Winchester used to employ.) A small advantage of Loctite is it has superior gap filling qualities similar to epoxy resin adhesives. Superglue works well, although I had the shop experience of a hard whack in very cold weather breaking the bond. Not a controlled test – Loctite might do the same for all I know. My late machinist Dad lectured me about using versions of Loctite other than blue on firearms. “Don’t use the “stud and bearing” grade because it’s made to hold for Eternity plus six months….”
- Bill
WACA # 65205; life member, NRA; member, TGCA; member, TSRA; amateur preservationist
"I have seen wicked men and fools, a great many of both, and I believe they both get paid in the end, but the fools first." -- David Balfour, narrator and protagonist of the novel, Kidnapped, by Robert Louis Stevenson.
November 7, 2015
Offline
There are literally dozens of variations of Loctite. The grade we want is one of the green ones, it resists loosening from vibration on threads and can be removed without heat or solvent. Actually silicone would probably work fine. I wasn’t kidding when I said I used a shim of normal Scotch tape on the bottom of a pistol sight. If one thickness isn’t enough a second will probably do. This is an EDC gun and has fired hundreds of rounds every year for several years. In fact, the tritium sights are fading so the simple little piece of tape has outlasted the sights.
Mike
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