Re: (TFT) Guns in TFT - A big expansion.

[Jay Carlisle <maou.tsaou@gmail.com>]

Old stuff I pulled real quicklike without type type as it's after midnight
and I'm wore out tired so better comment when coherent is somewhat closer
that what it is currently... and DeadSouls is taunting Me a bit I shant
lie... I have come to be quite the admirer of R.S. digits as functional
mechanics fwiw. Anyway, here tis. Don't even know if I found the bit about
bronze as art or cannon in the concerns of nations...


http://tft.brainiac.com/archive/0208/msg00059.html
A touch of research

According to John Wilcox in his Masters of Battle; Selected Great Warrior
Classes English Longbow men were capable of

firing 12 arrows per minute (1 every 5 seconds) at a range of 200 yards.
By the mid 14th century the English longbow far outranged the crossbow
generally effective to at least 200 yrds.
The bow was a single piece of wood (self bow) with a pull ranging from 100
to 185 lbs. and the ideal height was 4" taller than the bowman.
(This info from archeological evidence from the wreck of the warship the
Mary Rose sunk off the coast of the Isle of Wight in the early 15th century)


According to Donald Featherstone in his book "Weapons and Equipment of the
Victorian Soldier" The Martini-Henry rifle

(circa 1871) was the first firearm that could compete successfully with the
English longbow in range, rapidity of fire and

robustness.


Again from Mr. Wilcox. Before this a standard Dickert Kentucky rifle (circa
1750's, 60"+ in length and between .45 to .50

caliber, no standard as each was handmade) had a range roughly equal to the
English longbow (in many cases effective to 300

yrds).
However the longbow could fire about 5 times the arrows of the rifle at the
same range but the rifle accuracy was

significantly better.
The rifle however was preferred to be fired from a braced position.
Firing from an unbraced standing

position was called firing off handed or unprepared and is the source of
the phrase "off handed remark".
The Musket in comparison could be loaded at least twice as fast as the
rifle but its effective range was no more than 100 yrds.
Also 1lb of lead could form 16 .70 caliber musket rounds where the same
pound of lead yielded 48 .45 caliber rifle rounds.


<Hard to believe that some frontiersman, such as Simon Kenton, mastered the
ability to do all of this while running! -Dan>


I believe that Dan was referring to drills in which American "light"
Infantry were able to a man to hit a 7" target @ 250

yrds while in quick advance formation.
Also Isaac Miller, a frontiersman from Pennsylvania where 6 of the first 12
U.S.  regiments were drafted, was the fastest shot in his county who could
load and fire his weapon off handed in 26 seconds.

Loading a rifle took over 20 motions even allowing for time saving
procedures such as holding tears between the fingers of

the left hand while holding rounds in the mouth or even having a board with
holes drilled through it at the same diameter

as the rounds so that the round and tear could be stuffed into the holes
and the entire thing could be held over the bore

and rammed home in a single motion (basically a primitive magazine).


The statistics should speak for themselves. Take it for what it's worth.



http://tft.brainiac.com/archive/1008/msg00016.html
Cannon and Economics

Data dredged up from various sources and far from complete.

1.75 inch bore - 3 foot long - 150 pound weight - half pound shot

4.75 inch bore - 10 foot long - 1500 pound weight - 12 pound shot

6 inch bore - 12 foot long - 3000 pound weight - 24 to 26 pound shot

7 inch bore - 10 foot long - 6500 pound weight - 42 pound shot - 1.5 mile
range

8 inch bore - 8 foot long - 8000 pound weight - 63 pound shot

75 pound shot at a quarter mile range



Cast cannon main features.

Cascable or button

Breech

Bore

Base ring and ogee (ogee; a concave indention running adjacent to
reinforcing rings)

Vent field (touch hole)

Vent field astragal and fillet (astragal; a convex = to > inch circle,
fillet; concave junction)

First reinforce

First reinforce ring

Second reinforce

Trunnions

Second reinforce ring and ogee

Patch for foresight

Muzzle astragal and fillets

Swell of muzzle

Muzzle mouldings

As a rule of thumb a guns bore is about a third of the total diameter at
the breech to about half the total diameter just before the muzzle swell.


Features like the button, ogees, astragals, and fillets were often
decorated but also allowed for rigging and moving the pieces with block and
tackle.


Various forms of copper, bronze, and brass were used in cast form through
the early eighteenth century while lombards were made from strips of iron
(strakes) held together by iron bands every 4 to 6 inches along its length.


Cast iron guns began appearing in the late sixteenth century but were
subject to catastrophic failure causing shattering of the barrel into
shrapnel instead of splitting (especially around the breach) like a
Lombard.
Owing to this (as well as significant access to copper and tin) in 1599 a
royal order in Spain decreed that all gallons carry only bronze cannon and
all merchantmen had to carry at least 2 bronze pieces.

By 1725 cast iron cannon were the standard.

Casting is generally simpler and quicker than forging and iron is cheaper
than other gun-metals, and casting methods tend to lead to some
standardization.


The early guns we're talking about are smooth bore, black powder weapons.

There was a notion with these pieces that range was proportionate to the
length of the barrel.
This is true for modern artillery, and small arms of the period, but not
possible for these early guns.
The decomposition reaction in black powder has a burning rate that is
essentially independent of temperature and, above a quickly reached
threshold of about 350 psi., of pressure, or in the neighborhood of around
64 ST for black powder pressure. When black powder explodes, it increases
in volume about 4000 times at normal pressure, so the effect is to produce
a highly compressed gas behind the cannonball in a very short time.
The products are 40% gaseous, and 60% solid.
The solid fraction is expelled as a dense white smoke, which gives away the
position of a battery as soon as it is fired. The combustion of gunpowder
does not depend on atmospheric oxygen, because the oxidiser, saltpetre, is
part of it.
Ergo propellant gasses in a black powder weapon expand at a relatively
constant rate.
Experiment showed that for a twelve-pound field gun an absolute velocity
threshold was reached at a barrel length of about 25 calibers (25 times the
bore diameter).
Data indicated, moreover, that extending the barrel length beyond 16
calibers resulted in a gain in muzzle velocity of only about 5= per cent
while extending it beyond 12 calibers yielded only about a 12 per cent
gain. Due to the effects of aerodynamic drag, which increases as a function
of the velocity squared, these increases in muzzle velocity would have
resulted in even smaller increases in range. Additional factors such as the
coarser grain of black powder, the larger charges, and greater windage (the
difference between the size of bore and ball) also show that muzzle
velocities of sixteenth-century cannon were not a direct function of barrel
length.
Nevertheless many sixteenth-century cannon (including all of the culverins
except perhaps Venetian ones) had barrels considerably longer than the
length which would have produced the greatest muzzle velocity but this was
for added strength and safety rather than for ballistic purposes.

Design proceeded almost completely empirically.

For example, French gun makers cast a 58 caliber gun for Charles V that was
found to have poor range so it was progressively cut down to 43 calibers,
gaining a significant range increase in the process.
Another test recounts a 36 pound gun 16 calibers in length (about 8.5 feet
long) that was loaded with a powder charge one and one-sixth times the
weight of the round dropping in muzzle velocity from about 1300 fps with a
charge equal to projectile weight to about 1100 fps.
Even today black powder chemistry and gunmetal metallurgy are not fully
understood.
Modern theory suggests that on the whole, sixteenth century cannon had a
thickness roughly 50% greater than needed for strength. Founders of the
time however were not working with any well-articulated theory. The
stresses exerted by the powder charge are largest in exactly the sections
of guns that were cast thickest.
The sixteenth-century cannon founder felt that he was best off using a melt
of 80 per cent copper and 20 per cent tin, ignoring the 3 to 5 per cent of
impurities of which he was generally aware, but about which he could do
little.
We have no theoretical basis for believing that he was wrong.
European guns were cast muzzle up (with a clay core to make the bore, the
Turks put the muzzle down), and tin tends to migrate and cool last in a
bronze mix typically leaving muzzles more brittle, ergo thicker.
The rule of thumb for powder charges in the 16th century was a powder
weight equal to projectile weight.
That right there says I'm looking for effective range rather than a maximum
for shots involving gunning Talent.
Also worth mentioning, 12 pounders and smaller tended to target crew and
equipment with heaver guns firing at structure.


Ship construction (or building in general) is going to have a lot to do
with all of this, but I'd be curious about any thoughts on cannon from the
peanut gallery.


The actual acquisition of the materials required to produce guns and powder
are separate technological and economic issues. See the kings right to
stable earth in England or France, or the island of Nauru (just over 8 sq.
miles in area and largely blocked from guano export until 1907 because of
German claims in the south Pacific), or Chile's Pacific war that landlocked
Boliva, or the u.s. guano act of the 1850's, or etc., etc., etc.

Too much of a resource likely leads to economic Dutch disease.

=====
Post to the entire list by writing to tft@brainiac.com.
Unsubscribe by mailing to majordomo@brainiac.com with the message body
"unsubscribe tft"