doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Hot barrels, barrel construction, and other stuff

I have several questions for those more knowledgeable than I.

Is it possible to melt "soft-soldered" ribs off a new SxS or O/U (assuming that the gun was manufactured correctly) through high-volume shooting such as consecutive rounds of doubles on a hot summers day in Arizona or while shooting doves in Argentina?

Additionally, why are target model O/Us "hard-soldered" in lieu of "soft-soldered"? Is it due to the heat they will be subjected to during competition shooting or due to the "sheer" strength needed securely hold the barrels in the mono-block?

I am of the opinion that even after excessive shooting, the gun would become literally too uncomfortable to handle and/or shoot before the soft-soldering would melt enough to separate a rib. Furthermore, when ribs do separate, they separate for a variety of reasons such as barrel obstructions, barrel vibration, barrel flip, a manufacturing defect, etc... --and not necessarily "heat".

Am I misguided in my thinking?

Thanks in advance for your answers and Happy New Year.

Best,

David

PS: And for those of you who follow some of the other "smaller" boards, I think you will understand why I am asking this question.

Hi David. It is not possible to melt the solder from firing the gun.

With ordinary tin/lead solder 356°F is the point to be concerned about. I seriously doubt you are going to still be holding on to a gun when the bbls are that hot. 356° is the eutectic point (that point at which the entire mix goes from solid to liquid at the same time) of tin/lead at a mix of 66/34% respectfully. Any other tin/lead alloy will have a higher total melting point but will still get mushy & lose strength at this temp.There are of course soft solders of other alloys than strictly tin/lead which may have higher melting points, such as some of the lead free soft solders.

At 350F wouldn't raw steel (depending on the type) be a faint straw color ?

I have seen belt-feds with barrels hot enough to be a dull dark red, but with a break action or sporting shotgun I can't see how you could get a barrel 350 F.

Interesting question. One that I've wondered about on occasion. A study is in order. I would think the shotshells would be capable of heating barrels beyond 361F or the 375F melting point of more common 60/40 solder. But until someone either melts a set or takes some temp readings, it'll just be supposition.

You guys seem to be echoing my understand of soft soldered barrels and heat.

But then how would you read this post from a more experienced person than I,

"Anyone familiar with trap and skeet O/U guns from the 1950's and earlier that had soft soldered barrels has seen or heard of a set of O/U barrels losing a rib or seperating from getting too hot, especially during long strings of doubles. It does not happen much anymore, because the gun manufacturers went to high strength brazing to elliminate the problem. So lets please not rehash this. Its a historic fact. I do not know where you got your ideas or info, but all I can say for me is been there--seen it. High strength, high heat brazing solved it. End of problem."

This comment seems like an old-time myth to me... But then again I was not around in the 50s and still in diapers in the 60s. I bought my first shotgun as a 14 year old in 1980. So, by virtue of my age, I did not have the opportunity to shoot soft-solder guns during the 50s, but this claim seems to be totally counterintuitive to my understanding of double barreled shotguns and the way they are made.

Am I missing something?

David,
Anyone that has been to Yuma with a sxs for the Sept openner will attest their concern about this. Just standing in the sun with your gun, the barrels will get to a couple hundred degrees. Of course that's only about 80 degrees above the air temp. Then start shooting flurries and you get the picture.

I've participated in the UP SxS Classic several times. There's a one-man flurry event with 70-odd targets in 2 1/2 minutes. Don't think I've ever seen a rib come loose as a result of that event, and I'm not sure how much hotter you could get a sxs. You can only load and fire so fast, and it seems to me that if you were to get into the 200 range, even with a heavy glove on the leading hand (which most guys wear), you probably would not be hanging onto a gun with a splinter FE any more. And that's a lot faster shooting than a string of doubles in a trap or skeet event, because in those, you're waiting for the other guy(s) to shoot in between your own shooting. (I'd add that in the UP event, just about all the participants are using loaders--which increases their rate of fire significantly. Sometimes two loaders: one on either side, for each barrel.)

Considering the kindling point of walnut is probably below 450 degrees F. and since it is covered with oil or poly it sounds like you might not melt your barrels because your wood will be on fire.

Black powder burns hotter than smokeless and the barrels on a gun shooting BP loads are almost untouchable during a normal skeet round. Shooting BP rounds at a faster rate than that in a SxS with soft soldered ribs with the likelihood of them melting and we wouldn't have many of the old guns around in original shape anymore. If the solder were to be at or near the melting point, so would the plastic shell casings, paper caseing would at least be charred, plastic sight beads would deform or melt and wooden forends would flame. It's not much of a trick to get the excess oil in the forend of a fast fireing firearm to smoke under the right conditions, but bringing a set of shotgun tubes up to 350-400 degrees by fireing is. Soft solder isn't perfect and not all solder joints are either. They do have voids, faults and barrels do flex somewhat on fireing. A firearm is a machine and they do breakdown and need repair. Ribs do get loose..
As for high strength high heat brazing solving the problem..I recently fixed another loose rib on a single barrel gun that was originally attached at the factory with 'high strength high heat brazing'. Both repairs were done with soft solder and are still running fine.