How to TIGHTEN a front dovetail site?

[Col. Batguano]

Brass shims will be a little grabbier than aluminum. I make them out of used cartridge cases, and anneal and flatten the strip. They are around .010 thick. Easy to file down to the correct thickness, and of course they will get dark when they tarnish. Aluminum doesn't get black like brass does. I find the strips out of aluminum cans to be harder to work with than brass, though I have used it for shimming rifle scopes.

 

[crockett]

I've done them all, so let's review:
1. The first way was to use a center punch and make 4 dimples on the top of the barrel to push the metal down against the sight. The only problem is you'll never get the 4 dimples lined up right and some will be deeper than others (normal skills assumed) so it doesn't look very good.
2. Next time I used the center punch on the bottom of the dovetail to raise little rings or craters. This works fine.
3. Then I tried the shim. I just used paper to see how it would work. Worked fine. I tried aluminum foil and thin brass and that works too but believe it or not, the plain paper seemed okay and I finish my browned barrels with linseed oil so I just used an Exacto knife to trim off the excess paper and soaked all with oil. NOW I admit I don't want to tote my rifle around in a down pour of rain and I try to keep it dry, that said, I've never seen any rust under the paper shim.

 

[MIOutdoorsman]

You guys are awesome. I really appreciate the collective knowledge here, and the willingness to share with newbies like me. I have a few options to try now, and I'm pretty confident that at least some combination will work!

Thanks to all who have contributed, even if I didn't reply specifically to your post. I read everything here more than a few times and I appreciate everyone's ideas.

 

[M. De Land]

What thickness of shim stock do you need ?

 

[MIOutdoorsman]

I’m not sure what thickness will be needed yet. I purchased a shim gauge per above from Harbour Freight but I haven’t had a chance to see what will work best.

I know that I will need to cut the gauges so that they will fit in the wedge (currently too wide) and was planning on just cutting off a piece of the right thickness gauge and use it as the shim.

Is that reasonable?

 

[Black Hand]

Cut a strip as wide as the bottom of the dovetail (muzzle to breech) but wider than the base (side to side). Place the strip in the dovetail, slide in and center the sight then trim off the excess that hangs over (with thin material, you should be able to score it with a sharp blade/point and work it until it snaps). The strip is cut long because it may slip when you tap in the sight and if you cut the piece as large as the bottom of the sight, it may not have stayed in place (unless you soldered the shim piece to the bottom of the sight, but then you're back to previous suggestions). Once the sight is where you want it, lightly peen the edge of the dovetail to lock the sight in place.

 

[Dane]

For Pete's sake. This is NOT. A big deal.
Do like Eric says.... turn the sight upside down, and expand it slightly. Tap it in place. If it needs a little more, a rounded punch on the top till it locks in place.
This is starting to sound like a congressional hearing.
3 pages of dissertation over a loose front sight.
Just get on with it.

 

[Davemuzz]

Just remember, if none of the above works (which I'm sure it will) Harbor Freight sells bigger hammers. :rotf:

 

[Obi-Wan Cannoli]

Yes, I would try to cut the width without cutting the gauges completely off the case, this way you still have a complete feeler gauge after the project.

Also, you want to use the shimming material to create a friction fit to hold the sight in place, don't use any glues, adhesive tapes, solders, etc.

 

[Pete44ru]

Aluminum doesn't get black like brass does.

FWIW, brass turns black instantaneously with an application of cold blue.

 

[M. De Land]

You can shim under neath but it raises the sight in the over size dovetail and leaves unsigtly gaps at each end between the sight skirt ( if it has them fore and aft) and the barrel top. The best method is to do as I described and shim the top of the angled sight dovetail shoulder, bend a tab to hold the shim to the sight as it's driven in then score and break it off flush with the edge of the dovetail slot and sight body.
This forces the sight down to the bottom of the dovetail slot in the barrel and closes most or all of the gaps from being to large. It also makes the fix disappear.
I've mill cut and fit many sights over the last almost 40 years and know where of I speak.

 

[MIOutdoorsman]

UPDATE: I followed Obi’s recommendation and stopped at my local Harbour Freight on the way home from taking my kid to swim practice and I picked up a shim gauge as he recommended.

These shims were of varying thicknesses, and all of them were made from steel except for one brass one. No idea why they had one brass one, but sure enough, that one was the right thickness for my front site dovetail! I trimmed off a small piece, placed it in the dovetail, and was able to tap the sight right into place nice and snug. A sharp razor blade and a few back & forth bends took off the little tab that was sticking out, and Boom! I’m all set!

Again””thanks for all the suggestions fellas. My hat is off to all of you.

 

[M. De Land]

Well good, sorry you had to ruin a feeler gauge set to get as shim.

 

[Adui]

Feeler gauges are cheap enough. Even I could afford that fix. :hatsoff:

 

[Obi-Wan Cannoli]

It's not really ruined, most standard feeler gauge sets (including the one at Harbor Freight) nowadays come with 2 .010 gauges: one steel one and one brass one, it's the only gauge you get two of.

[internet look up side track] The brass one is used to set a reluctor air gap on engines where a non-ferrous metal is required due to magnetism or something. Which if he was careful with the cut he may still has enough gauge to perform that function.

 

[necchi]

sorry you had to ruin a feeler gauge set to get as shim.

Actually(?), Bargain store feeler gauges are a great place to find shim stock.
Sure, we can all buy the bigger sheet set's from Brownells for $20+ shipping per kit,
Or $2.99 and walk out the door and find the .375x375 piece ya need with lot's left over
:wink:

 

[nhmoose]

Well good, sorry you had to ruin a feeler gauge set to get as shim.

NOT a feeler gauge set it was bought as a variable size shim set. :surrender:

 

[M. De Land]

I have the assorted size Brownell's shim stock set and plenty of cut offs in a surplus can under the lathe I was going to give him if he had answered the thickness question but he has it taken care of now.

 

[Scota4570]

"For Pete's sake. This is NOT. A big deal.
Do like Eric says.... turn the sight upside down, and expand it slightly."

Agreed, I turn the sight upside down and tap a round mark on the edge in the middle, with the side of a punch and a hammer.

Put a piece of paper in the slot.

Leave the barrel alone. Peening the barrel slot edges, or worse, marking it up with punch marks and cold chisels hashes looks terrible and can not be repaired easily.

Very bubba.

 

[deandeib]

I recently tightened my 32 Pedersoli rear sight dove tail slot using a recommendation I found here on the forum. I took 16mm, 3/8 drive socket and laid it in the slot and whacked the socket with a hammer. I was very conservative and after three hits, checking after each hit, the sight went in very snugly and is secure in the dove tail. Absolutely no marks on the barrel from my peening. But after the sight was initially removed before my peening operation, I did see where the factory must have peened the front lip of the dove tail. since I bought the gun new from Cabela's in 1996. BTW, this operation was brought on by my replacing the basically useless buckhorn sight with a Lyman 16 AML sight. Sight height, range elevation adjustment and dove tail dimensions are perfect for this rifle.