With regards to gunsmithing, am i right thinking that silver soldering is actually a form of braising? what temperature is needed for silver soldering and what sort of equipment is used? Do you guys you the small self contained propane DIY torches or something more powereful? How much danger is there of ruining the temper of the barrel or what ever is being soldered?
Regards,

Peter

SOLDER melts in the 400F range ,Silver containing solder such as 95%tin,5% silver may be used without damaging temper of steel .BRAZING alloys melt in the 1100-1300F range, some of these contain silver .They will definitely destroy the temper. Propane torch is used for solder but brazing ,except for small parts, requires oxy/acetylene.

Pete E Silver hard soldering now called brazing, is still called silver soldering by we old timers. There are silver brazing alloys which reach liquidus as low as 1065 F. Most rifle barrels are tempered about 100 degrees above that and depending on the alloy even at higher temperatures. The danger is in the use of these alloy joining metals by the inept and clueless. For many years there were ramps made to be brazed on. I made enemies by refusing to braze these or any front ramps on barrels often in spite of the how to instructions the wannabe customer waived belligerently in my face. Reduced area pieces which go on the barrel a considerable distance back from the muzzle and where the barrel has more wall thickness is a different story. Sling studs and extra recoil lugs for example. Winchester in the M-70 Pre 64 brazed on the front ramps, including the small muzzle featherweights.
AFTER the front ramp was in place the barrel blank was bored,reamed and rifled. Same story with their 458 barrel recoil lug. Some of these were done after and in great haste and a few barrels were ruined in the process. The how to can be learned, but it is best to go through a lot of scrap learning, rather than MAKE it in learning.

The only thing I use silver solder for any more is to braze a carbide insert to a turning or boring bar. Way too much heat to make me happy. The alternative is to use Brownell's "force 44" This stuff is great and when done properly will not come loose I have even used it on add-on recoil lugs

I'm a Force 44 believer on guns..not silver solder..no place for silver solder except for certain jobs wherein it does not effect the action or sensitive parts as to temper etc. I prefer a tigged on bolt handle, but reharden the cam slot..

Thanks for the info guys,

So how were ribs attached to the older double shotguns/rifles?? Low temp soldering or high temp brazing/ silver hard soldering??

Away from gunsmithing and in a more general work shop situation, can you braze using a decent propane torch (not one of the small DIY ones) or do you need something hotter?

Regards,

Pete

Pete , on shotguns a express SXS rifles the chopper lumbs barrels are silver brazed by the plane at the chambers , the ribs are soft soldering , in a express it's more important as you need to de-solder to adjust the barrels covergence and solder again .

Best regards

Daniel

Pete E Well, it doesn't look like you intend to give up, a spirit I tend to like, so....
Shotgun barrels first, It was an art in the UK to utilise what was known there as "Lead burning", I don't know why that term, it's probably a British thing. Almost pure lead was employed as the joining agent. It appears that the parts were first tinned by using a solder, then applying the lead to the tinned parts. I learned how to "weld" lead plumbing special "crapper" joints- a form of elbow connecting the throne to the cast iron system pipe- but that procedure though similar does not work. Shotgun double barrels joined this way can be blued in the common immersion bluing bath because the alkalye solution eats tin and not lead. The Spanish seem to be the ones who silver braze barrels together regularly, or at least did so. About 100 years ago when there were problems soft soldering sights on the S M L E rifle of the time the problem was handed off to one of the Universities, I think Manchester, but might have been Leeds, at any rate an absolutely thorough bit of research was done and the results obtainable after WW I through His Majesty's Printing Office. This entailed more combinations of the baser metals + silver than can be believed, and either a companion piece or a follow up detailed the same for the "Hard solders" which we know now as brazing alloys and Eutectics. You might search the webb, for this info and check out Johnson -Mathey's site about silver bearing brazing materials. You can employ ordinary Propane torches for soft soldering, but the secret of silver brazing is that heat which is necessary to the task applied liberally and quickly and once the"solder" melts capillary action takes over and you are done and can quickly
draw off the heat in the parts with "chill bars", but not water until the parts will no longer sizzle spit. I rarely use my Victor Oxygen/acetylene torch any more, instead use a Dillon which is a short and handy welders torch invented in Australia and was sold world wide. It is probably now banned in Australia as well as California because it looks like a pistol complete with scarry looking hoses connected to the 2 gas cylinders. A Mapp gas outfit will work ,but silver brazing usually requires more heat sooner, and Acetylene can provide it. If you get started doing this form of joinery, When you get feeling cocky try brazing copper to Aluminium. Should you succeed you can be one of the very few persons in the UK capable of doing this. If you get no where with a webb search, reopen this thread and I'll add some more.

Pete,
Your question about general shop torches. The best hand torch IMHO is the Turbo Torch. They aren't cheap, but they work with Propane or Mapp gas. I have brazed small dia. tubing using propane, but Mapp gets the job done faster. if you want to go one step up the next best thing is an air/acetylene torch. With a turbo tip you can silver braze about anything.
I'm not a gunsmith, I do HVAC work so I have a great deal of experience with soldering and brazing.
As for low temp melting solder for disimiliar metals Harris Stay-Brite 8 is about as good as you can get. The only drawback is the cost about $30lb. US.

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