[modeleng] Re: new website
- From: "Jesse Livingston" <fernj1@xxxxxxxxxxxxx>
- To: <modeleng@xxxxxxxxxxxxx>
- Date: Thu, 22 Nov 2007 18:49:44 -0600
Tony,
Black powder comes in several granulations as you probably know. The ffffg
being the finest , fastest burning and is intended for pistols. Muskets
used ffg as a rule and generate a slower combustion so that should work just
fine. I still would fire the thing with a heavier ball and charge
accompanied by a looooong fuse the first time. I would light the fuse and
go around behind the barn to admire the rutabaga blossoms until it fired the
first time. It sounds like it will hold, but with cast iron, one is never
sure.
My 1860 Ordnance manual (US) says that the large cast iron Columbiad
seacoast cannons would burst, but no one could predict when it would happen.
Sometimes they burst on the third shot, but the author knew of one that had
fired over 1,300 times and was still in one piece. I would imagine that
artillerymen kept a tight you know what every time they fired one of the
things, because it WAS going to burst sooner or later. He went on to show
via some drawings exactly why it would burst and showed a design that was
supposed to be as perfect as possible against bursting. The barrel had to
be perfectly rounded with no ornamental rings cast on it nor should it have
a cascable or its trunnions cast as part of the barrel. Trunnions were to
be made of bronze and fitted to the barrel with a sort of bridle like
affair. Guns made to this pattern proved to be pretty near burst proof,
even more so than the Brooke style with shrunk on wrought iron bands like
the "Long Cecil" breech loader of Boer War fame.
Jesse, the former CSA Artilleryman and waver of Confederate flags when
possible.
I have a Southbend Colonial field cannon at 1:10 scale, in cast iron with a
stainless steel liner, and it weighs a lot less than 17lbs! It still have a
.600" bore though, so that I find 20-guage shotgun solid ball and wads
"would be" ideal ..... but I didn't say that! <VBG> 70 grains of black
powder goes well in a .577" Enfield musket, and so should be about right
for
this cannon of mine. Weight for weight, for similar recoil, a charge of
120 - 140 grains would be about right for a 17lb barrel, so about an inch
bore perhaps?
I would stay away from shotgun cartridges though, as they have different
impulse / pressure curves due to their nitrocelluse based smokeless
powders,
unless you use a steel liner, which then becomes the barrel and chamber
with
the brass tubing just there for show ....
Tony.
MODEL ENGINEERING DISCUSSION LIST.
To UNSUBSCRIBE from this list, send a blank email to,
modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.
Other related posts:
