doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Steel inserts for an old Darne

Jose,
I would think silver solder would be a better choice. You would need to be careful, as the barrel tubes are held into the monobloc with silver solder, but, if worse came to worse, you would take it all apart, clean the solder joints in the tubes and resolder the whole thing back together. The gun could probably stand a rib relay anyway, at this junction in time.

I would be hesitant to use glue to hold the sub tubes into the bores of the old barrels.

Good luck.

Best,
Ted

Graded approach
The liner can not exit the muzzle, they are only 18 inches long and fitted
to the bored out barrel.

The liner is held from exiting the rear of the barrels by the breech face

So try the Locktite and if the liners should move then go with the silver solder
That will require great caution and re-bluing

Mike

Rifle liners are held in place with Locktite. Soldering is almost never done in the last couple of decades due to the improvement in adhesives. Shotgun liners should be even easier to glue in place.

You might want to read about how a good gunsmith does a similar repair operation. It would seem this repair was done fairly recently ( less than a couple decades ago).

https://vicknairgunsmithing.blogspot.com/2022/12/correcting-excess-headspace-in-parker.html


Best,
Ted

I've no doubt it works, but it won't look or perform one bit better than what other really superb gunsmiths do.

Ted, that Parker chamber repair by Dewey Vicknair was amazing. But I'm not surprised.

I think either solder or the correct adhesive should work if the fit of the sub-gauge tubes to the bore is close. I used a Loc-Tite retaining compound to replace the hardened valve seat in a lawn tractor engine, and even with that sort of heat, it never moved in roughly 15 years. I merely roughened the loose valve seat with a small carbide bit in a die grinder and did the same to the recess in the block. 18" long tubes have many times more contact area. And for that same reason, if Jose chose to go with solder, I'm sure plain old 60-40 tin lead solder would be more than strong enough. Plus there would be less risk of melting the solder joints in the monobloc.

I have no experience with the very low melting point Tin-Bismuth solder alloys, so can't comment.

He’s essentially making a chamber mate from scratch.
Why doesn’t someone with a machinist’s talent get out their mics and help the man out.

There’s no reason to reinvent the wheel here.

Just saying

Might be just the thing for the diy gunsmithing section.

The old gauge 12 gauge chamber and pitted barrel bored out a bit for 18 inches
Then a THIN WALL insert is fabricated and placed in the barrel to give a new
20 gauge chamber, forcing cone and leade configurations.

https://chiappafirearms.com/product.php?id=565

The extractor must be modified to 20 gauge

Thank you, as always, for your good advise!

Probably the "ortodox way" to fix the inserts is silver soldering, but I do not know a person that do the procedure nor I have the knowledge to do it myself, so I will try the "Locktite method"

I think I am still several weeks away of the "final product", buy I will continue to work in the project as times allow me.

Best regards,

Jose

A choke maker that has done work for me over the years before he had the .410 tap would sleeve chokes and secure them to the barrel with Loctite. I had one made up for a friend over 10 years ago and it still holds fast. Gil