Author Topic: Swivel gun (Read 4516 times)

grymster · « **on:** February 04, 2010, 09:16:43 AM »

Hi, name's grym and I'm a newb here.

Came across these forums while looking for information on black powder cannon making. For my first project I'd like to make a swivel gun and I'm hoping some of you can answer a few questions. I have modeled up a gun that's about 3.5" diameter at the breech, about 20" long with a tentative 1" bore. I'd like to make it of brass, but I'm not entirely committed to that.

So:

Seems to me a mortar has a powder chamber that is smaller than the bore diameter; would the same be true for a cannon such as a swivel gun? Or is a hole of single (caliber) diameter bored and the space behind the ball serves as the powder chamber?

Many of the cannon and swivel guns I've seen have a series of bands cast or machined onto the OD of the barrel; are there some sort of rhyme or reason for their number, size and/or spacing? Or are they purely aesthetic?

I've seen some cannon with offset trunnions; what might be the advantage of that?

I did the modeling in SolidWorks and I'm currently experiencing a computer problem that won't let me access my model. Hope to have that issue resolved soon and maybe I'll post some images.

Double D · « **Reply #1 on:** February 04, 2010, 10:02:23 AM »

I suggest you get a copy of Building 18th Century Naval Artillery by Damian Siekonic. He covers build Swivel guns in his books. Some very clever tricks and ideas to help you with your build.

Howitzers and mortars had powder chambers. Swivels didn't.

Those bands are reinforcing bands some are functional and some are decorative.

Below centerline trunnions were abandoned in favor of centerline trunnions to reduce muzzle flip in recoil.

If you a free form designing your own cannon, then you should acquire a copy of John Muller's A Treatise of Artillery 1780. Muller lays out proper form as a series of ratios relating to the diameter of the bore. This allows you to come up with correct barrel diameters and lengths, trunnion locations, etc. Muller extend those realtionships to carriages and bases also.

You also want to take a look at the two references in our safe loads and cannon plans sticky at the top of this board. Both N-SSA and AAA provided minimum standards for loads and design.

Zulu · « **Reply #2 on:** February 04, 2010, 10:05:05 AM »

Double D is right. Anyone can make a pipe with a hole in it. If you are going through the trouble, you might as well make something historical and shoots safely.
Zulu

brokenpole · « **Reply #3 on:** February 04, 2010, 10:10:26 AM »

gyrm,

Welcome to the board!!!

Just keep posting your questions. There are many folks here with a lot of expierence building these things. You mentioned pictures of your design. Those would be appreciated by all that read this forum. Also pictures as you commence the build up to and including smoke and fire pics when you swivel is finished.

So again welcome...no for the disclaimer...the owners and moderators of this forum along with all who post and read threads contained here in are not blamed or held responsible for your actions should you decide to build a working cannon or mortar. This is an addiction with no known cure (other than to purchase and/or build more and more up to and including a mortar that shots 5 gallon water jugs filled with cement).
The short version...you are on your own.

Enjoy!!!

dan610324 · « **Reply #4 on:** February 04, 2010, 11:04:34 AM »

from the messurements you mentioned it would give you a 17-18 cal deep bore , that mean a semi modern barrel to me , the older the barrel is the longer they should be to be time correct
here you got some approximate barrel lengths and years ( just a rule of thumb )
1500 - 1600 30 cal bore length ( some more )
1600 - 1700 25 cal
1700 - 1850 18 cal

www.arkeliet.net is a very good place if you want to learn more about cannon proportions
lots of original drawings

the proportions of the field lengths and band placement are very strict if you want a propotional correct barrel

all messurements are set in calibers or parts of caliber ( mostly 1/8 )
as an example the trunnions diameter and length should be the same as the bore diameter
same with the cascable

grymster · « **Reply #5 on:** February 04, 2010, 11:22:47 AM »

Thanks all.

On Double D's advice I'll be ordering a copy of Building 18th Century Naval Artillery. Even if I never build a cannon, I think I'll like reading it.

While my current model is freeform, I did base it on images and the bit of technical information I could glean. I do intend for it to be at least mostly historically accurate and of course, safe.

Quote from: dan610324

from the messurements you mentioned it would give you a 17-18 cal deep bore , that mean a semi modern barrel to me

Other than the fact I've been shooting black powder revolvers for a few years and like designing and machining stuff, I'm about 20 books into Alexander Kent's Bolitho series and all the talk of swivel guns in those books reminded me that I need one. Given the novels start in the late 1700's, I think the shorter bore would be appropriate. Maybe that's why I accidentally designed it that way!

Quote from: dan610324

www.arkeliet.net is a very good place if you want to learn more about cannon proportions lots of original drawings

I plan on learning Norwegian, just as soon as I master English!

But thanks for the link; I'll dig through it.

Quote from: brokenpole

You mentioned pictures of your design.

I hoping to have my computer fixed tomorrow, but will post images of the model as soon as I can in any case.

dan610324 · « **Reply #6 on:** February 04, 2010, 12:00:11 PM »

you dont need the norwegian to check the proportions on the drawings

click on the word "bildearkiv" in the upper right corner of the screen
when you come there scroll down to the bottom , there you find the artillery handbooks with the drawings
click on the book you want to look at
all drawings are enlargeable by clicking

most of the writing on the drawings are in german

here is an pdf of a barrel that I designed , all proportions are correct for a mid 1600 barrel except the bore diameter , I reduced it from 16,5 mm to 13 mm just to make it a little bit stronger
scroll down and check them , its 4 drawings

GGaskill · « **Reply #7 on:** February 04, 2010, 01:12:09 PM »

Many of the cannon and swivel guns I've seen have a series of bands cast or machined onto the OD of the barrel; ...

The early guns were made from forge welded strips and the rings around the barrel were functional reinforcements that strengthened the tube. As the barrels became cast instead of welded, the various bands became more decoration and less function.

There is a video on the internet of a couple of blacksmiths making a barrel by forging, including the placing of the rings on the tube. Very interesting. Maybe this one.

grymster · « **Reply #8 on:** February 04, 2010, 01:54:24 PM »

Nice drawings Dan!

Thanks for the link GGaskill; just the audio would make it worthwhile!

RocklockI · « **Reply #9 on:** February 04, 2010, 02:31:10 PM »

If you are going to make one you might as well find an origanal to copy more or less . Old bronze guns rule IMHO but hang out for awhile .

The questions you asked were good ones , but after learning abit you'll find something or other that really grabs you.

I like swivels and small guns in general .....although some swivels were not small at all .

Grab a coffeetable type book on old artillary ,or other soure as well as the sometimes dry resources available .

Gary

ETA welcome this IS the place

RocklockI · « **Reply #10 on:** February 04, 2010, 02:47:35 PM »

George thats an awsome video ...

may have to watch this several times . I did like the way they cut out all the reheating and forge stuff ,just assy and forge welding . It can be humbling to realize how little of the basics we still know . Is there no longtitudinal support ? it cant be just a stack of welded rings can it ? What about 'staves' running length wise ?

I will never be an ironsmith ,lord knows getting copper and tin to melt is hard enough .

Cannoneer · « **Reply #11 on:** February 05, 2010, 05:39:56 AM »

Welcome aboard, Grym! The history of swivel guns is long, and the profiles, sizes, and materials used in making them varied. This video was posted by a member a while back, and it shows some examples of swivel guns from around the world.

navygunner · « **Reply #12 on:** February 05, 2010, 11:22:37 AM »

Wow!!! Talk about a walk thru a candy shop!!!!

NG

carronader · « **Reply #13 on:** February 05, 2010, 11:43:20 AM »

or..............you could melt those rinkie dinks down and make a real gonne.

GGaskill · « **Reply #14 on:** February 05, 2010, 01:31:20 PM »

it cant be just a stack of welded rings can it ? What about 'staves' running length wise ?

The staves are the bottom layer that is welded together. The rings are exterior reinforcements for the staves.

seacoastartillery · « **Reply #15 on:** February 05, 2010, 02:22:54 PM »

Quote from: GGaskill on February 05, 2010, 01:31:20 PM

it cant be just a stack of welded rings can it ? What about 'staves' running length wise ?

The staves are the bottom layer that is welded together. The rings are exterior reinforcements for the staves.

I watched that video of the blacksmithing of the 15 Century breech loading cannon several times and I am quite sure that no welding occurred before the fellow in the light blue shirt slid those two yellow-hot rings down around two, clam-shell, half tubes. In fact, if you watch very carefully, you can see daylight through the two halves as the glowing rings slide downward. It is possible that I misunderstood where the welding occurred, but I can't see any in this clip. Maybe that very brief, two second, part where the blacksmith tried to burn up his vernier calipers showed the welding?? GeorgeG, can you shed some light on where the welding is done to the tube please?

Thanks, love that clip!!

Tracy

GGaskill · « **Reply #16 on:** February 05, 2010, 02:49:09 PM »

I'll have to look at the video. I was speaking more from my understanding of history than from observation of the video.

seacoastartillery · « **Reply #17 on:** February 05, 2010, 02:57:59 PM »

I understand completely, George; thanks for looking into it.

Tracy

RocklockI · « **Reply #18 on:** February 05, 2010, 06:08:12 PM »

Wasnt it hammer welded and 'forged' together with the repeated smashing (hammering) of the beat down slide hammer .

KABAR2 · « **Reply #19 on:** February 06, 2010, 11:50:26 PM »

Quote from: RocklockI on February 05, 2010, 06:08:12 PM

Wasnt it hammer welded and 'forged' together with the repeated smashing (hammering) of the beat down slide hammer .

The beating down of the rings is not forge welding they are being shrunk onto the tube the inner metal is cold

the heated outer metal slips over it and as it cooled shrinks and locks into place.

the making of the rings out of bar stock and hammer welding the ends together would be forge welding.

GGaskill · « **Reply #20 on:** February 07, 2010, 06:39:37 AM »

Looking at the video you can easily see a seam in the tube. Almost seems like they rolled a piece of flat plate since only one seam is visible but that part is not in that video.

grymster · « **Reply #21 on:** February 11, 2010, 06:48:36 AM »

Well, I still haven't fixed my computer. I have a Mac and run SolidWorks on a VMWare virtual machine. VMWare hangs up just before fully booting. But, the last thing I was doing on it was working on my swivel gun model, so I'm able to take a screen shot of that particular view. I currently have the trunnions off center and plan to put them back on center. I think I need to elongate the "neck?" (not really up on cannon nomenclature) and maybe mess with the muzzle. Again, it's about 3.5" at the breech and 20" long. I'd welcome any comments, suggestions, critiques.

Oh.... I couldn't wait, so I have a little 30 caliber barrel coming from Brooks to help sustain me while I work on my own.

KABAR2 · « **Reply #22 on:** February 11, 2010, 08:42:06 AM »

Proportions look good I would say you are well on your way,

Quote from: grymster on February 04, 2010, 11:22:47 AM

I'm about 20 books into Alexander Kent's Bolitho series and all the talk of swivel guns in those books reminded me that I need one. Given the novels start in the late 1700's, I think the shorter bore would be appropriate. Maybe that's why I accidentally designed it that way!

That's a good series of books I enjoyed reading them back in the late 70's & 80's and quite a time line from midshipman to admrial,
everyone when talking about the British navy and the age of sail always go to Hornblower I think kent has taken it much further.

dan610324 · « **Reply #23 on:** February 11, 2010, 08:45:50 AM »

also if your norwegian aint the best I still recomend you to check out the drawings on arkeliet

check the proportions for where to place reinforcement rings and trunnions
or maybe copy an original swivel

but its you who should be pleased with the result
what other people think and say aint interesting ( me included )

grymster · « **Reply #24 on:** February 12, 2010, 04:10:18 AM »

Quote

That's a good series of books I enjoyed reading them back in the late 70's & 80's and quite a time line from midshipman to admrial,
everyone when talking about the British navy and the age of sail always go to Hornblower I think kent has taken it much further.

I haven't read Hornblower yet. Last I looked it was not available for the Kindle. Meanwhile, despite some disappointments, I'm enjoying the Bolitho series.... think I'm on #22 now.

As for my swivel gun design; should I keep the stepped look on the muzzle face, or go with a flat look? Or maybe a flare?

MikeR C · « **Reply #25 on:** February 12, 2010, 09:13:23 AM »

THIS is a swivel gun

carronader · « **Reply #26 on:** February 12, 2010, 09:18:49 AM »

all this fuss over a titchy little tube on a stick...........use these.

grymster · « **Reply #27 on:** February 12, 2010, 10:43:04 AM »

Quote

THIS is a swivel gun

Bah.... looks like a breech loader!

GGaskill · « **Reply #28 on:** February 12, 2010, 10:53:47 AM »

It is. The early ones were breechloaders. They used a removable piece like a thundermug that held the charge.

grymster · « **Reply #29 on:** February 12, 2010, 11:31:40 AM »

It is pretty cool.

Thought I saw a miniature one around here somewhere.

Thanks for the drawings, carronader!