Why did they use octagon barrels so much?

[MBTcustom]

All forged finishes I ever saw looked like a blacksmith made it with a hammer.

No offence, but you obviously haven't spent much time with a mastersmith.
Even hypodermic needles were made on a coal fired forge back in the day. A mastersmith is capable of extremely even surfaces, round or flat, that need little more than a layer of carbon to be polished off.

[GOPHER SLAYER]

I have allways thought you could make a barrel lighter if you ground it in an octagon shape. Wasn't that the idea?

[Molly]

... A lathe for turning something round was not something a small shop would have. ...

John, haven't you ever heard of a spring-pole lathe? In a spring-pole lathe, the rotation was provided by a tough pole with a rope attached to the top, and the other end of the rope attached to the metal (or wood) stock to be worked. A foot pedal arrangement allowed the craftsman to step on the pedal to spin the metal (or wood), and the spring pole rewound it when the craftsman lifted his foot. It wasn't fast or high precision, but it was cheap, and most of those guys had a lot more time and ingenuity than money.

The same sort of arrangement could be used to power jig saws, drills, etc. They used what they had on hand to use, or did without.

That reminds me of a story I heard of how one guy ground the flats on his octagonal barrels. The guy was also a miller, and owned a water powered mill. His mill had an arrangement whereby a barrel was dropped into a slot at the end of the workday, and the mill was left running to turn a grindstone against the barrel. When the flat had been ground the entire length of the barrel, the barrel dropped free to hit a small lever that opened the sluice, and stopped the mill, thereby preventing excessive wear on the mill.

My hat is off to those old timers. I doubt if half of us could do half so well.

[John Taylor]

You might be able to find the video " Gunsmith of Williamsburg" at the library, it shows making a barrel by welding full length and talks about why octagon.

[paul h]

I have allways thought you could make a barrel lighter if you ground it in an octagon shape. Wasn't that the idea?

That is incorrect, the lightest possible barrel will always be round. You have to have a minimum wall thickness to contain the pressure in the barrel, and in the case of an octagon barrel, that will be the thickness across the flats.



Hence the round barrel with the same minimal wall thickness will be lighter than an octagon.

[KCSO]

Your other consideration is the ease of inletting an octagon barrel with primitive tools. It is easier to let on in square than a round barrel, you sure can't put a square across a round barrel and see if you are square. Same with dovetailing, try and put a dovetail square into a round barrel without a jig sometime. Remember your old time gunsmiths did it all by hand with planes and scrapers and hand drills.

[Texantothecore]

The octagon barrels have a lot of extra steel in them because it was assumed that any new rifle would be occasionally rebored to a larger caliber to eliminate pits and problems in the original bore. Which they did on a pretty regular basis. Many men owned their grandfather's flintlock and they worked fine for their lifetime and were handed down to their kids.

Most rifles of that period that measure .36 or so started out as .32 squirrel rifles.

By the way, an 8 groove barrel required 276 set ups on the rifling engine to cut the rifling. Really expensive. Which may explain the deep grooves in the rifling. The grooves would not have to be recut if the bore was enlarged.

[Texantothecore]

Their tools were extremely manual. They used hand planes to inlet barrels, etc. Many of the gunsmiths were also furniture makers and if you look at their probate records it is very difficult to tell if someone also made guns. The most reliable indicator is probably a rectangular billet of iron (not steel) and perhaps a part in a box from a broken lock.

[MBTcustom]

That explanation needs explanation!

The octagon barrels have a lot of extra steel in them because it was assumed that any new rifle would be occasionally rebored to a larger caliber to eliminate pits and problems in the original bore.

I don't see how having an octagon barrel gives you any advantage over a round barrel of the same diameter as the measurement across the flats, especially because the barrel flats do not "twist" with the rifling.

Most rifles of that period that measure .36 or so started out as .32 squirrel rifles.....Really expensive. Which may explain the deep grooves in the rifling.The grooves would not have to be recut if the bore was enlarged.

I've never heard of this as being definite fact, but I'll take your word for it.

By the way, an 8 groove barrel required 276 set ups on the rifling engine to cut the rifling.

Could you elaborate on this a little bit? I know what a rifling bench is, and I assume that the "rifling engine" is the automated sort that was driven by the overhead mandrel in old factories. I have studied the rifling process lightly, and I was under the understanding that cut rifling required one set up to align the barrel with the axis of the cutting rod, and simply rotating the barrel to cut each groove a few ten-thousandths of an inch deeper each time. I would not really call each time the barrel is indexed a "set up" as it required nothing more than pulling the indexing pin and rotating the barrel 45 degrees and repeating the cutting process. If you are referring to some process other than using a sine-bar rifling bench, I would like to know what it is and how it works.

[Wayne Smith]

I'm guessing, Tim, that each time paper was added to the rifling jig to deepen the cut is what he is calling a 'set-up'.

[waksupi]

I'd have to question some of the information, too. I've built several hundred muzzle loaders, and never used a plane of any sort to inlet a barrel.

The more I read those previous posts, the more BS I see in them. Where did you get this stuff? Throw that book away.

[Idaho Sharpshooter]

www.schifferbooks.com has this neat book by John Rice Irwin called "Guns and Gunmaking Tools of Southern Appalachia". $14.95.

Page 28 has your answer, a sort-of anvil called a Swage Block or Gun Anvil.

They date back at least 400 years, in Europe; and likely came here as early as 1720 with settlers like the German/Moravians, etc.

They are generally square or slightly rectangular, with up to ten or twelve octagon or round or square notches cut around the edges. There are also a number of cutouts inside the block of varying sizes. It was probably used to insure a square or octagon barrel was straight, before pulling the mandrel out. Some sizes were to make mandrel rods for different calibers. One pictured has a slight curvature on one side, to make and repair the iron hoops on wagon wheels.

Rich
Knowledge not shared is knowledge lost.

[Texantothecore]

That explanation needs explanation!

I don't see how having an octagon barrel gives you any advantage over a round barrel of the same diameter as the measurement across the flats, especially because the barrel flats do not "twist" with the rifling.

I've never heard of this as being definite fact, but I'll take your word for it.

Could you elaborate on this a little bit? I know what a rifling bench is, and I assume that the "rifling engine" is the automated sort that was driven by the overhead mandrel in old factories. I have studied the rifling process lightly, and I was under the understanding that cut rifling required one set up to align the barrel with the axis of the cutting rod, and simply rotating the barrel to cut each groove a few ten-thousandths of an inch deeper each time. I would not really call each time the barrel is indexed a "set up" as it required nothing more than pulling the indexing pin and rotating the barrel 45 degrees and repeating the cutting process. If you are referring to some process other than using a sine-bar rifling bench, I would like to know what it is and how it works.

First of all, the barrels were not steel but iron, very soft fully annealed iron. They needed more mass to contain the explosion successfully. Many shooters would use two balls and twice the charge if hunting deer and they were able to do so without any problems.

As far as the rifling engines go, they were made of wood and had multiple grooves cut into the wood to guide the cutting iron. The cutting iron was made of steel, rather soft by our standards but adequate to the task of cutting the grooves rather gradually following the grooves on the rifling engine. The cutting was done by hand, not using water power or other power sources and was a lot of work.

The first groove was cut.
The rifling engine was either turned or the cutting tool was moved to another groove on the rifling engine. After eight cuts (on an eight groove barrel), a small sheet of paper was placed underneath the cutter deepening the groove slightly for the next eight cuts. This continued until the rifling was finished.

Lots of set ups. On the other hand, these guys worked very quickly and it probably took less time to groove a barrel than we would think these days.

As far as the octagon barrel is concerned there are many arguments in its favor involving the manufacturing process. You can simply file the flats, no machinery required and it is easy to file the flats to the point that the bore is in the center of the barrel. And because they didn't have any machinery other than the manual rifling engine. I mean No Machinery whatsoever. Just hand tools. As I stated in a previous post, most of the gunsmiths were also furniture makers and their equipment listed in probate records are mostly furniture manufacturing equipment. Many of the gun known gunmakers also have been crossferenced to furniture and gunsmithing advertisements in the local broadsheets.

As far as lapping out a muzzleloader to repair the bore, it was done all the time. These were lifetime guns and many of them were handed down over the decades to children and grandchildren as working guns, not novelties. Many of the cap and ball guns that we see these days started their lives as flintlocks and were modified to accomodate the cap and ball action if the owner wished.

My comments are based on an interview of a very elderly man (95) who was a gunsmith in the early 1800s and possibly a few years in the 1700s. The author died in the 1920s at an advanced age due to a blow up of one of his old guns.

[MBTcustom]

I have seen the rifling benches that you refer to as "engines". The ones I saw operated on the same principle as the sine benches did (ie the barrel was indexed in its holder). Yes it was fairly labor intensive, but the sine style cured much of that. The real hard part was grinding the cutters in such a fashion as to get the most life out of them.
I believe that the old smiths knew exactly what they were doing, and had better understanding of machinery than the average jo. Think they couldn't figure out how to make a sine bench? cast your gaze a little rearward of the barrel, and observe the lockwork. I don't mean just the simple chunky flinters, but also the multi-barrel double trigger jobs. Not trying to question your friend or you, but I just don't get how a gunsmith would be so cleaver with lockwork and delicate mechanisms, and yet be so crude with the rest of the equipment of his trade. I know that the wooden benches existed, and were probably used by poor gunsmiths, but I also think that there were gunsmiths that had advanced equipment. I think it was just like it is today. Most gunsmiths are armorers (ie parts changers), and then there are a few who have what it takes to build from scratch. I would think that a local gunsmith back then would make a fairly good bit of profit from reborring barrels for folks. However, making the blanket statement that "most of the gunsmiths were also furniture makers and their equipment listed in probate records are mostly furniture manufacturing equipment. " is a bit simplistic. I think that some communities had no metalworker so they had to make do with what the carpenter could come up with, but I believe that there were many communities that had a fully fledged gunsmith operating with apprentices and everything. If you knew how to work metal, and had aspirations of being an armorer, you went to the big city to find employment. Just like today, if I want to work on state of the art defense equipment, I have to move to the big city for both the education and the job.

[Texantothecore]

I am sure that you are right. /Out.

[KCSO]

I saw a barrel channel plane in a German book on gunsmithing and built one and it works fine on the right wood. I will try and find the book again so I can post a drawing. I also have a fore stock shaping plane and scraper.

As to recutting a barrel that is a simple operation that does not require a rifling machine. You cut the grooves deeper with a cutter let into a lead lap cast in the bore of the rifle. Each pass you add a piece of cigarette paper to deepen the groove. After all grooves are the same depth you then cut down the lands with a reamer and a lap.

[MBTcustom]

KCSO, I would love to see pictures of that stuff!
Texantothecore, please don't go away mad, I meant no disrespect or harm. I was just thinking out loud. I'm trying to get my head around the your point of view, but its coming hard because it contradicts other things I have learned over the years. I have changed my opinion on many different subjects here on cast boolits by throwing what I know on the thread and letting it get torn to pieces until I find out which end had the bone in it.

[Texantothecore]

Ok, I'll come back in on this discussion. No offence taken.

Just think of how you would make a flintlock with:

No electricity

No water wheel to power your equipment. Water mills were expensive to build and probably ran in current USD say, 500,000 to 1,000,000 to build and involved buying a least an acre of land for a pond above the mill to allow them to regulate water flow as well as an exit area below. Investment capital was very difficult to come by and usually whatever capital was available was family money. In otherwords, not much. Guys who were already rich built water mills, not young gunsmiths.

Steam was unavailable and the steam hammer was not invented until 1808. Took a good decade to make them commonly available.

Iron is very soft and at least one report I have read is that the gunsmith could cut the flats with a steel edged drawknife. Very possible as pure iron is apparently softer than aluminum.

Most of the examples we have in our museums have English, Dutch or French locks on them and it is thought that this was quite normal. Making a lock without power by hand is a bit difficult. The locksmith smoothed out the action and mounted the lock but that was about it. Appalachia, however, had some locksmiths who made their own locks. I believe the Peeples or Peebles family did their own locks. The lock distribution industry was quite large and it stretched from New York to the smallest trading posts in the West. Tens of millions of locks passed through these distributors over the years. Which was part of the problem with Bellelisle's work. He didn't know about the lock distribution system in the US and apparently a lot of the records still exist.

Making a flintlock is not really a high precision pursuit. Everything was adjustable and they were adjusted to be reliable shooters. View cameras are the same. A fixed back camera such as an SLR is quite high tech, view camera can be made with the tools in your garage.

I spent 35 years in manufacturing and I became fascinated with the wonderful machinery the Victorians invented during the 19th Century. They were very innovative and much of that machinery, except for the addition of that new fangled electrical engine thingie, is much the same.

So. Another .02 for the info mill.

[MBTcustom]

I suppose I was thinking of 1700s and later.
My experiance is coming from building my own forge and using nothing but hand tools to produce flame hardened steel knives and tools. Even a piece of cold rolled steel or iron will become refined and infused with carbon if it is folded several times and welded in a coal forge. I have studied hand craftsmanship extensively and I have made many tools and knives by hand with a coal forge. Why? because I literally could not afford better tools. I made my first smoothbore caplock pistol when I was 13 years old, using only hand tools (OK I cheated and used a hand drill to drill the bore) and I made another when I was 14. I came to the conclusion that there is little to no money in handforged knives and implements, and decided to go to school and learn how to make things with modern machinery. I worked my way up through the trade, and at my last job I was running the wire EDM department (3 new machines as of 2006) and the heat treat department (5 ovens, one nitrogen purged). This whole time I continued to stay involved with gunsmithing and saw the value of merging my education over a coal forge with modern machinery.
I say all this to say that I know very well what hand tools are capable of, and hand operated machinery. That's why I am having trouble seeing why they would have trouble with some of the machinery that I mentioned earlier (although admittedly, I may be taking certain modern conveniences for granted).
The early rifling benches were made of cast iron and were driven by hand. Its just a more efficient method of doing the same work as the wooden rifling "engine" (which constitutes a "machine" by my estimation). It is true that iron can be scrapped by hand with a hand plane (its basically a single edged file), and I don't doubt for a minute that they used such an implement to make the flats on the early barrels.
I didn't know about the locksmiths being a specialized trade unto itself. Interesting information, although, I can tell you that pure iron is harder than aluminum, but they didn't have any such material back then.
Henry Maudslay invented the modern, geared head, screw cutting lathe in 1797, so what century are you talking about? What I suppose I should have said, was that I was wondering why they cut flats on the barrels when they obviously had metal cutting lathes long before Henry decided it would be useful to gear the apron to the head and make it possible to cut screw threads (by the way, Maudslay's lathe was made of iron, not wood.)
What is the advantage? Why go to all the trouble?
By the way, thanks for coming back into the discussion!

[Longwood]

I saw a barrel channel plane in a German book on gunsmithing and built one and it works fine on the right wood.

I have only done two stocks from scratch.
I made a little aluminum plane and it worked well for parts of the job.
I made it with a block of aluminum that had a rounded and flat edge and a blade that was ground to work on either side.
It was a pain to use in some ways and needed to be redesigned.
These, would be nice to own.

http://www.ebay.com/itm/14pcs-Mini-e...item27c99ce66b