This has probably already been discussed before, but anyway, How much welding can one get by with on rifle barrels?

Today's chrome moly barrels are mostly 4140 and the welding requires special techniques and equipment to do so...specifically pre heating...

While it may be safe for some to do so I'd not want a barrel that has been arc welded or MIG welded in any manner....

Possibly some folks can electron beam weld on a barrel..... I know for a fact that some of the military components are welded and they are using maraging steel but this is real hi tech stuff

Short answer....don't do it.

correct answer...
NOT VERY MUCH...

tig or mig to anchor (not attach) a recoil lug is probably okay...

but if you make a soft spot, or harden the barrel, you can ruin accuracy.

jeffe

quote:

Originally posted by 22WRF:
This has probably already been discussed before, but anyway, How much welding can one get by with on rifle barrels?

What did you have in mind?

Wouldn't suggest it. Welding causes minute distortion, or even major depending on how much welding is done, and as Jeffe said, it's extremely possible to mess with the temper of the steel. Chrome-moly, which the industries' standard these days is 4140, is a higher-carbon steel which is a little more difficult to weld than a lower carbon steel. If you're talking about stainless, most notably 416R which a majority of barrel makers use, you can forget about it.
Unless if you want to do some funky stuff, like maybe inertia or ultra-sonic welding, or maybe even laser welding (highly doubtful), that would be considered a very unlikely and very doubtful possibility.
Best bet I'd say is just to use duct tape buddy!

It's also interesting that some of the "sky is falling" because of the stress induced or relieving of stress caused by recontouring folks are not using that here where serious stress is induced by welding.

But of course at least one of them isn't here right now.....

One can easily take a fringe concern and "lewinsky" it to extremism but that don't do the science and art of gunsmithing any good.

While it's still the case that I'm not in favor of any welding on a rifle barrel for both metallurgical reasons and accuracy reasons it shouldn't be construed to say that there are not reasonable applications where it's both reasonable and prudent to do so. I just can't see one right now.

I actually did extensive arc welding on a rifle barrel some time ago and fired it without damage to anything but my pride. The barrel warped so badly that one could actually not see thru the 30 caliber hole and it was only 20" long.

I used a hydraulic press to straighten the darn thing and the barrel was fired without incident.

It was a very stupid thing to do but it did suggest that one could do a minor amount of welding on a barrel and get away with it.

quote:

Originally posted by malm:

quote:

Originally posted by 22WRF:
This has probably already been discussed before, but anyway, How much welding can one get by with on rifle barrels?

What did you have in mind?

Well, I was going to put a cantilever on a shotgun barrel for scope mounting but I don't have very much faith in solder to hold it on there and I don't want to drill holes in a real thin shotgun barrel. I was thinking a few tacks here and there would hold it.

quote:

Originally posted by 22WRF:
How much welding can one get by with on rifle barrels?

quote:

to put a cantilever on a shotgun barrel

22, you should learn to have more faith in solder.

quote:

Originally posted by 22WRF:

quote:

Originally posted by malm:

quote:

Originally posted by 22WRF:
This has probably already been discussed before, but anyway, How much welding can one get by with on rifle barrels?

What did you have in mind?

Well, I was going to put a cantilever on a shotgun barrel for scope mounting but I don't have very much faith in solder to hold it on there and I don't want to drill holes in a real thin shotgun barrel. I was thinking a few tacks here and there would hold it.

Disclaimer: When needed, I prefer to use solder on barrels.

That said, I have on special occasion, used a TIG welder to tac welded front sights to tactical shotgun barrels. Special care was taken to protect the bore and keep the heat localized during the job. Even at that, a small amount of distortion is possible. If you prepare the area carefully and provide as much protection as possible during the tac welding, you should be fine.

I have seen factory barrels who's bores were out of whack and puckered from soldering so the potential for damage isn't necessarily limited to welding.

If you are intent on welding on the barrel, I would recommend using a TIG on as low a setting as is needed, and I would use a liberal amount of Brownells Heat Control paste in the bore and on the surrounding areas during the tacking process.

Were it me doing the welding, I would break the arc and keep the nozzle of the torch over the weld and let the gas blow directly on the weld to provide protection while the weld cooled below the "glow". I wouldn't quench the barrel with it still glowing. Once the glow has disappeared, then I would apply a soaking wet rag to the area to cool it to the touch. At this point, I don't believe you would need to reheat the weld, or, surrounding area to neutralize it. You should be fine. You might find an old scrap piece of shotgun barrel to practice on. If you need one, send me your address and I'll send you a short piece of shotgun barrel.

Good luck!

quote:

Originally posted by 22WRF:
...Well, I was going to put a cantilever on a shotgun barrel for scope mounting ...

Haven't looked in awhile, but you should be able to find an Aftermarket barrel or a Factory barrel with it already mounted for maybe $200 or so new. Go to a Gun Show and you might trip on to one for $100.

Get youself some Hi-Force solder, and the flux to go with it, from Brownells. Done properly, that cantilever ain't goin' anywhere soon!

quote:

Originally posted by vapodog:

quote:

Originally posted by 22WRF:
How much welding can one get by with on rifle barrels?

quote:

to put a cantilever on a shotgun barrel

22, you should learn to have more faith in solder.

I meant to say "Rifled" barrels. sorry for the confusion.

quote:

Originally posted by 22WRF:
Well, I was going to put a cantilever on a shotgun barrel for scope mounting but I don't have very much faith in solder to hold it on there and I don't want to drill holes in a real thin shotgun barrel. I was thinking a few tacks here and there would hold it.

The issue with "Solder" is the ambiguity of the term...

To Disabmiguate a bit there are two distinctly different types of solder:
A)"soft solders" comprised principally of Tin, Lead, Antimony.
B)"hard solder" usually comprised of some combination of Copper, Tin, silver and sometimes Cadmium.

Some people refer to the second type as "silver soldering" which is the cause of the confusion, call it "brazing" alleviates the ambiguity.

Low temperature BRAZING won't hurt steel because the melt and flow temperatures are too low to materially affect any heat treating.

and gun barrels are invariably made in their annealed condition anyway, toughness is far more desirable in a gunbarrel than outright hardness.

So if you are looking at mounting a cantilever
on a barrel the proper method is by low temperature silver brazing.

I personally recommend using 56%Silver cadmium-Free material as it has the lowest melting point, and is frequently cheaper than lower silver content brazing compounds, because it's
generally the most common, reason for that is it is the ONLY silver brazing material that is approved for "sanitary" (food grade) brazing, on stainless steel.

It sticks REAL WELL to most substrates, as it is the silver content tha makes "Hard solder"
stick (with soft solder it's the tin)

AllanD