I have a 20g Fox SW. Bbls are uncut, but the bottom 1/3 of the hour glass-shaped fillet between the bbls at the muzzle has been pushed down into the space between the ribs. The ribs are totally intact and ring true. I'd like to fill the hole in and was wondering if I could drop a bead of solder in then stone it flat.
My concern is the melting temp of the solder used originally to lay the ribs. Last thing I want to do is melt that and face having to get them repaired/relaid.
I bought a tube of silver solder last pm that was marked low temp (420), but I'm thinking if Fox used lead/tin it probably has an even lower MP. . . I wanted to check w/ you all before going down this road. How would the pros do it?
Any advice?
Thanks,
Bill

Brownells sells a low temp solder that melts at 275 degrees. Or you could put some heat control paste on the ribs to keep them cool. I have made small spot repairs on ribs by making heat sinks to keep the area past where I am working from getting too hot. Used dry ice on one job with wet cotton to make a safe area which heat I was using could do no harm to the rest of the gun. It is all about keeping a minor repair from becoming a major disaster as you have said. But minor repairs can often be done with what you have if you take precautions to keep the bores and ribs cool.

Bill, I had a Fox with the same problem. I mixed up a little
JB WELD,filled the opening ,then blended it in with a little sandpaper.It was almost impossible to detect.

I use a small jeweler's torch and low melt solder. Want to watch? I am in Earlysville behind the airport.

I use a small jeweler's torch and low melt solder. Want to watch? I am in Earlysville behind the airport.

Sorry, hit the submit twice.

Clean up the end and the sides of the cavity with a sharp instrument to get a good clean base for the new solder to hold. Flux it with a Non corrosive flux and using an electric soldering gun ( I use a common Weller pistol grip type) you can seal it up in nothing more than a few seconds time with no fear of disturbing the ribs at all. No flame to worry about, nice and clean. No need for clamps, heat sinks, wire wraps, etc. Just tin the soldering gun tip well, use the high heat if it has one and add a bit of solder if needed. If the cavity is extra deep (or was open ended), a small tuft of clean steel wool tucked down in there will take up some space and also provide some extra strength to the solder. If it were open ended, it would prevent the solder from running down into the space and instead would fill and plug the end as needed. Clean it off with a file instead of a stone as a stone will just fill with the lead and become useless. Do the final trim with grit paper backed with a file to what ever polish you want. Keep it square!
BTW that solder you bought will work fine, it's just silver bearing solder, same as Brownells Force 44 is. The melting temp is more than OK for the job but most any lead/tin solder will do. The silver bearing solders will stay bright and not turn that dark gray shade like the lead/tin solders do though.
True silver solders have melting points in the 1000* range +/- and are not what you're looking for in this case.

I wouldn't solder anything.
Take a small piece of lead (a .22 bullet would do) pound it flat 1/8" thick, cut a piece just slightly larger than the area to fill, lay in on the muzzle and lightly tap into place with a brass hammer. I'll bet it will last longer than you do.

I second the recommendation for JB Weld. I have done it and it looks fine.

Well, you can't beat the offer that Prof Apperson made.

If I had the problem I'd go the traditional route and wire the end together like re-laying and use rosin flux and a propane torch. It takes only a few minutes to wire the ribs/barrels and it gives confidence that you won't mess up and loosen the ribs.

Wow! This is about the best post I have ever seen for great answers! Seems like you have quite a few good choices to choose from, Bill. Good luck.

This is maybe a dumb question but Kutter's post made me contemplate the following: Kutter recommends a small tuft of steel wool in the hole and then solder on top of it. How does the gunmaker solder the end shut with nothing behind the opening?

Steve,
I just did this when re-laying the ribs on some barrels. For an openning of more than an 1/8", fitting a small piece of steel into the hole is typical. It's usually a small triangle. At least it is on the Parker I took apart and other American doubles I have. This Lefever barrel rib has that triangle silver brazed to the rib.



On smaller holes, simply tilt the barrels muzzle down about 10 degrees, play the torch on the area to get the heat right, and add solder. If you keep them level, the solder will flow into the barrel gap and you'll end up adding more and more solder without getting the end filled and built up.

Another way I filled the end during sleeving was to machine a hourglass shaped piece and solder that in.

Wow! I was away from the computer this weekend and am amazed at the great response.

You all may be familiar with this book already, but I found an incredible resource yesterday at a local antique shop-Modern Gunsmithing by Clyde Baker c 1933. Was up half the night reading it. He mentions the insertion of tight-fitting cotton to plug the void pressed about an inch in from the muzzle, then pouring zinc chloride into the hole and then decanting it out. Next, soft solder is melted and poured into the hole to fill and filed off. Same idea as the steel wool, but not sure where the Zn comes into play. Also, I'm not sure how widely this book was read, but Mr Baker may be to blame for the the hinge pin peening to bring guns back on face as he does advocate this for the "working man's" American double. Other than this though, sound advice and some neat period info including some chapters by Townsend Whelen, the developer of the 220 Swift I think.
BTW, I also picked up a copy of our own Steven Dodd Hughes' book on custom doubles (not at the antique shop). Great info as well--and interesting to read about how the grainy black blue rust finish was achieved on the Fox. Beautiful guns, too!

I haven't had a chance to do anything yet, but as I'm so close to Earlysville myself, if Prof Apperson is willing, I'd like to bring the gun to him (and also an orig Parker 28 I found to show off).
Thanks so much,
Bill

I've done this repair before using a torch and silver solder just like what is mentioned before. Not too hard, but not for the feint hearted either.

Just do not rush and remember to take the bead off!

I'm wondering why silver alloyed solder, with a higher melting temp than the original/existing 60/40 tin/lead solder, would even be considered? 60/40 solder melts around 364F. JMO, but I see no advantage in using anything other than the original alloy or a lower melting point solder.

Alot of the silver/tin alloy soft solder around melts in the 400F range and will work well but I agree that plain old lead/tin worked fine in the original application and no reason to look elsewhere for a fixer. Alot of the stuff around now is 'lead free' silver alloy soft solder and it's marketed as Silver Solder though it's not the silver solder I think of. Plus the silver alloy soft solder stuff will stay forever bright white and never tone down to the medium grey of the lead/tin stuff if thats a concern on an older gun for looks. It'll always look like a repair as will an epoxy plug, but they'll work OK of course. Using the older zinc chloride flux will get you a great solder bond even with a less than perfectly clean prep surface but it will almost certainly guarantee some very active after rust in there if the stuff isn't completely flushed out. Another step to add to what starts as a simple resoldering job. Clean the edges of the surfaces well, flux with a noncorrosive flux and a touch of solder with your favorite applicator (electric or torch) and you're done. I'd wire and/or clamp if using a torch (which I don't use anymore) as alot of heat is dispersed into the barrels and ribs even with a small flame. No need to, as I said, if using a soldering gun or iron. If it takes more than 30 seconds to do the actual soldering at the muzzle, you're doing something wrong.
If you want to add a triangle steel piece to the opening, take a piece of round stock big enough in diameter that you can file to a three sided, tapered spike that will not fall into the opening but the three sides will hang up on the rib and barrel edges. It doesn't have to be overly long inside (watch the length on top that it doesn't interfere with the front sight bead). Tin it, clip it to length so there is just a bit of extra to the outside, drop it into place, solder and face it off to the muzzles with the soldering job.
FWIW, the soldering iron or gun is perfect for tinning the ribs and barrels for relaying too.

When I say torch, I mean the Smith's small torch. It has five heads; the smallest three are sapphire tips.The flame of the smallest is about 1/32 ".They are most often used to weld the links of gold jewelry chains.The heat is the same as any oxy-acetlyene torch and one can get in and out very quickly.I can generally make a repair in less than 30 seconds. Bill