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DA: Abbreviation
for Double Action.
DAO: Abbreviation for Double
Action Only.
DAMASCENE: The decorating of
metal with another metal, either by inlaying or attaching in some fashion.
Damascene is often confused with Damascening or engine turning.
DAMASCUS BARREL: A barrel made by twisting, forming
and welding thin strips of steel around a mandrel.
DEBURRING TOOL: The deburring tool
removes burrs from the inside and outside of newly-trimmed case mouths.
DECAP: To deprime a case by
removing a spent primer from the primer pocket, most often accomplished by
the decapping pin in a die during the resizing operation of reloading.
DECLARATION OF INDEPENDENCE: Drafted by
Thomas Jefferson between June 11 and June 28, 1776, the Declaration of
Independence is at once the nation's (United States of America) most
cherished symbol of liberty and Jefferson's most enduring monument. Here,
in exalted and unforgettable phrases, Jefferson expressed the convictions
in the minds and hearts of the American people. The political philosophy
of the Declaration was not new; its ideals of individual liberty had
already been expressed by John Locke and the Continental philosophers.
What Jefferson did was to summarize this philosophy in "self-evident
truths" and set forth a list of grievances against the King in order to
justify before the world the breaking of ties between the colonies and the
mother country. You are invited to read a transcription of the complete
text of the Declaration of Independence below.
|
 |
| Note:
This image of the Declaration is
taken from the engraving made by printer William J.
Stone in 1823 and is the most frequently reproduced
version of the document. |
|
IN CONGRESS, July 4, 1776.
The original Declaration, now exhibited
in the Rotunda of the National Archives Building in
Washington, DC, is badly faded. Largely due to
the poor preservation techniques
employed during the 19th century.
Today, this priceless document is
maintained under the most exacting archival conditions
possible.
- High Resolution Images are
available -
These files are very large
(8 to 10 megabytes) and will take approximately 1/2 hour or
longer to download on a 56k modem connection. These images
will print at approximately 24" wide by 29" high at 300 dpi
(publication quality).
For graphic designers, each
file also contains "clipping paths" for easy mask creation
with most professional graphics software.
- For High Resolution Images -
Click Here - |
|
|
The
Declaration of Independence:
A Transcription
IN CONGRESS, July 4, 1776.
The unanimous Declaration of the thirteen
united States of America,
When in the Course of human events, it becomes
necessary for one people to dissolve the political bands which have
connected them with another, and to assume among the powers of the
earth, the separate and equal station to which the Laws of Nature
and of Nature's God entitle them, a decent respect to the opinions
of mankind requires that they should declare the causes which impel
them to the separation.
We hold these truths to be self-evident, that
all men are created equal, that they are endowed by their Creator
with certain unalienable Rights, that among these are Life, Liberty
and the pursuit of Happiness.--That to secure these rights,
Governments are instituted among Men, deriving their just powers
from the consent of the governed, --That whenever any Form of
Government becomes destructive of these ends, it is the Right of the
People to alter or to abolish it, and to institute new Government,
laying its foundation on such principles and organizing its powers
in such form, as to them shall seem most likely to effect their
Safety and Happiness. Prudence, indeed, will dictate that
Governments long established should not be changed for light and
transient causes; and accordingly all experience hath shewn, that
mankind are more disposed to suffer, while evils are sufferable,
than to right themselves by abolishing the forms to which they are
accustomed. But when a long train of abuses and usurpations,
pursuing invariably the same Object evinces a design to reduce them
under absolute Despotism, it is their right, it is their duty, to
throw off such Government, and to provide new Guards for their
future security.--Such has been the patient sufferance of these
Colonies; and such is now the necessity which constrains them to
alter their former Systems of Government. The history of the present
King of Great Britain is a history of repeated injuries and
usurpations, all having in direct object the establishment of an
absolute Tyranny over these States. To prove this, let Facts be
submitted to a candid world.
He has refused his Assent to Laws, the most
wholesome and necessary for the public good.
He has forbidden his Governors to pass Laws
of immediate and pressing importance, unless suspended in their
operation till his Assent should be obtained; and when so
suspended, he has utterly neglected to attend to them.
He has refused to pass other Laws for the
accommodation of large districts of people, unless those people
would relinquish the right of Representation in the Legislature, a
right inestimable to them and formidable to tyrants only.
He has called together legislative bodies at
places unusual, uncomfortable, and distant from the depository of
their public Records, for the sole purpose of fatiguing them into
compliance with his measures.
He has dissolved Representative Houses
repeatedly, for opposing with manly firmness his invasions on the
rights of the people.
He has refused for a long time, after such
dissolutions, to cause others to be elected; whereby the
Legislative powers, incapable of Annihilation, have returned to
the People at large for their exercise; the State remaining in the
mean time exposed to all the dangers of invasion from without, and
convulsions within.
He has endeavoured to prevent the population
of these States; for that purpose obstructing the Laws for
Naturalization of Foreigners; refusing to pass others to encourage
their migrations hither, and raising the conditions of new
Appropriations of Lands.
He has obstructed the Administration of
Justice, by refusing his Assent to Laws for establishing Judiciary
powers.
He has made Judges dependent on his Will
alone, for the tenure of their offices, and the amount and payment
of their salaries.
He has erected a multitude of New Offices,
and sent hither swarms of Officers to harrass our people, and eat
out their substance.
He has kept among us, in times of peace,
Standing Armies without the Consent of our legislatures.
He has affected to render the Military
independent of and superior to the Civil power.
He has combined with others to subject us to
a jurisdiction foreign to our constitution, and unacknowledged by
our laws; giving his Assent to their Acts of pretended
Legislation:
For Quartering large bodies of armed troops
among us:
For protecting them, by a mock Trial, from
punishment for any Murders which they should commit on the
Inhabitants of these States:
For cutting off our Trade with all parts of
the world:
For imposing Taxes on us without our
Consent:
For depriving us in many cases, of the
benefits of Trial by Jury:
For transporting us beyond Seas to be tried
for pretended offences
For abolishing the free System of English
Laws in a neighbouring Province, establishing therein an Arbitrary
government, and enlarging its Boundaries so as to render it at
once an example and fit instrument for introducing the same
absolute rule into these Colonies:
For taking away our Charters, abolishing our
most valuable Laws, and altering fundamentally the Forms of our
Governments:
For suspending our own Legislatures, and
declaring themselves invested with power to legislate for us in
all cases whatsoever.
He has abdicated Government here, by
declaring us out of his Protection and waging War against us.
He has plundered our seas, ravaged our
Coasts, burnt our towns, and destroyed the lives of our people.
He is at this time transporting large Armies
of foreign Mercenaries to compleat the works of death, desolation
and tyranny, already begun with circumstances of Cruelty & perfidy
scarcely paralleled in the most barbarous ages, and totally
unworthy the Head of a civilized nation.
He has constrained our fellow Citizens taken
Captive on the high Seas to bear Arms against their Country, to
become the executioners of their friends and Brethren, or to fall
themselves by their Hands.
He has excited domestic insurrections
amongst us, and has endeavoured to bring on the inhabitants of our
frontiers, the merciless Indian Savages, whose known rule of
warfare, is an undistinguished destruction of all ages, sexes and
conditions.
In every stage of these Oppressions We have
Petitioned for Redress in the most humble terms: Our repeated
Petitions have been answered only by repeated injury. A Prince whose
character is thus marked by every act which may define a Tyrant, is
unfit to be the ruler of a free people.
Nor have We been wanting in attentions to our
Brittish brethren. We have warned them from time to time of attempts
by their legislature to extend an unwarrantable jurisdiction over
us. We have reminded them of the circumstances of our emigration and
settlement here. We have appealed to their native justice and
magnanimity, and we have conjured them by the ties of our common
kindred to disavow these usurpations, which, would inevitably
interrupt our connections and correspondence. They too have been
deaf to the voice of justice and of consanguinity. We must,
therefore, acquiesce in the necessity, which denounces our
Separation, and hold them, as we hold the rest of mankind, Enemies
in War, in Peace Friends.
We, therefore, the Representatives of the
united States of America, in General Congress, Assembled, appealing
to the Supreme Judge of the world for the rectitude of our
intentions, do, in the Name, and by Authority of the good People of
these Colonies, solemnly publish and declare, That these United
Colonies are, and of Right ought to be Free and Independent States;
that they are Absolved from all Allegiance to the British Crown, and
that all political connection between them and the State of Great
Britain, is and ought to be totally dissolved; and that as Free and
Independent States, they have full Power to levy War, conclude
Peace, contract Alliances, establish Commerce, and to do all other
Acts and Things which Independent States may of right do. And for
the support of this Declaration, with a firm reliance on the
protection of divine Providence, we mutually pledge to each other
our Lives, our Fortunes and our sacred Honor.
The 56 signatures on the Declaration of
Independence appear in the positions indicated:
|
Column 1
Georgia:
Button Gwinnett
Lyman Hall
George Walton |
Column 2
North Carolina:
William Hooper
Joseph Hewes
John Penn
South Carolina:
Edward Rutledge
Thomas Heyward, Jr.
Thomas Lynch, Jr.
Arthur Middleton |
Column 3
Massachusetts:
John Hancock
Maryland:
Samuel Chase
William Paca
Thomas Stone
Charles Carroll of Carrollton
Virginia:
George Wythe
Richard Henry Lee
Thomas Jefferson
Benjamin Harrison
Thomas Nelson, Jr.
Francis Lightfoot Lee
Carter Braxton |
|
Column 4
Pennsylvania:
Robert Morris
Benjamin Rush
Benjamin Franklin
John Morton
George Clymer
James Smith
George Taylor
James Wilson
George Ross
Delaware:
Caesar Rodney
George Read
Thomas McKean |
Column 5
New York:
William Floyd
Philip Livingston
Francis Lewis
Lewis Morris
New Jersey:
Richard Stockton
John Witherspoon
Francis Hopkinson
John Hart
Abraham Clark
|
Column 6
New Hampshire:
Josiah Bartlett
William Whipple
Massachusetts:
Samuel Adams
John Adams
Robert Treat Paine
Elbridge Gerry
Rhode Island:
Stephen Hopkins
William Ellery
Connecticut:
Roger Sherman
Samuel Huntington
William Williams
Oliver Wolcott
New Hampshire:
Matthew Thornton
_ |
|
DECLARING: The process of
notifying an airline that you are transporting a firearm. See
Traveling with a Firearm for further details.
DECOCK: The process of
un-cocking or returning the hammer or striker to the down or forward and
unsprung position on a firearm.
DECOCK LEVER: A lever which
allows the gun to be decocked safely without pulling the trigger.
Also called a Decocking Lever or a Decocker. Most commonly found on
the SIG Sauer P series handguns and the new Heckler and Koch USP and
Walther P99 models.
DEFENSE:
A military combat mission exemplified by a coordinated effort by a
force to defeat an attacker and prevent the enemy attacker from achieving
there objectives.
Typical defensive missions are:
- Defend in
Sector: A mission which requires a defending unit to
prevent enemy forces from passing beyond the rear boundary of
the sector, while retaining flank security, and ensuring
integrity of effort within the scheme of maneuver.
- Defend a Battle
Position (BP): A mission which places a unit in
a BP to concentrate its fires, to limit its maneuver, or to
place it in an advantageous position to counterattack.
- Defend a Strong
Point: A mission which implies retention of the
position at all costs. Repeated assaults must be expected
and repelled.
|
DIE: A tool, in hand loading, that
reforms cartridge cases and seats bullets; or, in bullet manufacturing a
tool that swages bullets or cores, extrudes lead wire or draws jackets.
DERRINGER: A small
single-shot or multi-barreled (rarely more than two) handgun or pocket
pistol. See below.
The Derringer Pistol
DETONATE: To explode with great violence. It is generally associated
with high explosives e.g. TNT, dynamite, etc., and not with the relatively
slow-burning smokeless gun powders that are classed as propellants.
DNF:
Abbreviation for Did Not Finish as used in firearm competition to state
the shooter did not complete the course of fire.
DOUBLE ACTION: A handgun
mechanism where pulling the trigger does two actions; action one (1)
retracts the hammer or striker and cocks the firearm, and the second (2)
action releases the hammer or striker style firing pin to initiate
discharge. The opposite of Double Action is Single Action, where the
trigger only performs one action, that is releasing the cocked
hammer. All Single Action Firearms must be manually cocked.
Double Action Revolver:
In reference to revolvers, "double action" means that it may be fired by
just pulling the trigger to cock the hammer and fire the gun.
Double Action Pistols
(semi-automatics) can be cocked for the first shot by pulling
the trigger to cock the firearm, then fire the gun. The SIG P228
and Walther P38 are double action semi autos.
DOUBLE ACTION ONLY:
Double Action Only or DAO guns are those which are fired by using the
trigger to first cock the hammer and then fire the firearm for each shot.
Between shots, the hammer rests forward, uncocked. Many Law
Enforcement Agencies specify DAO side arms for safety and liability.
DOUBLE BARREL:
Two barrels on a firearm mounted to one frame. The barrels can
be vertically (over-under) or horizontally (side-by-side) aligned.
DOUBLE-BARRELED: A gun
consisting of two barrels joined either side by side or one over the
other.
DOUBLE BASE POWDER:
Smokeless powder made with nitroglycerine and nitrocellulose base.
DOUBLE TAP: A quick succession
to two-shots fired rapidly from a semiautomatic pistol, rifle or shotgun,
or a revolver. Also, as a verb, to describe the act of firing a
double-tap. When doing a double tap the shooter does not line
up (sight alignment or sight picture) the second shot. They
line up once, and then pull the trigger twice. For most shooters
(with some training) double taps can be practical and accurate at short
distances. In sport shooting competitions this can be a very
valuable technique for saving time by clearing close targets very quickly.
NOTE: Check with the staff at your local range before practicing
double taps. Some ranges do not allow shooters to fire more than one
shot per second.
DOUBLE-SET TRIGGER: A
device which consists of two triggers one to cock the mechanism that
spring-assists the other trigger, substantially lightening trigger pull.
DOVETAIL: A flaring
machined or hand cut slot that is also slightly tapered toward one end.
Cut into the upper surface of barrels and sometimes actions, the dovetail
accepts a corresponding part on which a sight is mounted. Dovetail slot
blanks are used to cover the dovetail when the original sight has been
removed or lost; this gives the barrel a more pleasing appearance and
configuration.
DOWN RANGE: The
direction shots are normally fired on a range. The area where the
targets are set up.
DRAG: 1. Something that retards
motion or action. 2. The retarding force acting on a body (as a
bullet) moving through a fluid (as air) parallel and opposite to the
direction of motion. 3. Friction between machined parts.
Also : retardation due to friction. In Gunnery and
External Ballistics the body or object effected by drag is the bullet or
pellets fired from a gun. The amount of drag varies depending on the
density of the air, the square of the velocity, the air's viscosity and
compressibility, the size and shape of the body [ projectile or bullet ],
and the body's inclination to the flow. In general, the dependence
on body shape, inclination, air viscosity, and compressibility is very
complex. One way to deal with complex dependencies is to characterize the
dependence by a single variable. For drag, this variable is called the
Drag Coefficient, expressed Cd. - See below for more
information on Drag and Coefficient of Drag.
|
What is Drag?
And How Does it Effect A Bullet In Flight?
By Matthew Mosdell of Lost
River Ballistic Technologies, Inc.
For a long time it
was thought that the only force a bullet had to overcome was the
force of gravity. Air was thought to have such a small influence on
the path of a bullet that it was not even involved with determining
early trajectories. Later, Benjamin Robins, using his ballistic
pendulum, showed that the air had an influence 85 times greater than
that of gravity on the flight of a bullet. Since that time great
effort and energy have been involved in trying to minimize the
effect air has on a bullets flight path. From the .75 caliber
monster fired by Robins to the sleek .308 shot by many hunters
today, drag has always posed a problem in accurately firing a rifle.
There are many
factors involved in understanding how air effects the trajectory of
a bullet; some of these include air pressure (altitude), humidity,
and temperature. All of these things effect the path of a bullet in
flight, and must be considered to accurately fire a rifle. Other
things that influence a bullets trajectory are the bullets shape,
its spin ratio, and its velocity. This discussion will mainly focus
on the laws of motion and how different forces (air pressure,
humidity, temp.) influence the path of a bullet.
Sir Isaac Newton
(1642-1727) was perhaps the greatest scientist of all time. One of
his greatest contributions to science, and the field of ballistics,
was his formulation of the three laws of motion. The three laws of
motion describe how things act with respect to gravity and forces
which act upon them.
Newton’s First Law of
Motion states:
A body remains at rest, or
if in motion it remains in uniform motion with constant
speed in a straight line, unless it is acted on by an
unbalanced external force.
Newton’s Second Law of Motion states:
The acceleration produced
by an unbalanced force acting on a body is proportional to
the magnitude of the net force, in the same direction as the
force, and inversely proportional to the mass of the body.
Newton’s Third Law of Motion states:
Whenever one body exerts a
force upon a second body, the second body exerts a force
upon the first body; these forces are equal in magnitude,
and oppositely directed.
Each of these laws will
help in understanding why a bullet behaves the way it does
while in flight, and how external forces effect the ballistics
of a projectile. |
First of
all, the bullet in the chamber is “at rest” and must be acted upon
to accelerate out of the barrel. This initial force is, of course,
the burning of the gunpowder, which causes the subsequent expansion
of gas forcing the bullet out of the cartridge, down the barrel, and
toward the target. Interior ballistics is the study of this process;
from primer ignition to the bullets exit from the barrel. The
bullets flight path out of the rifle is influenced greatly by many
variables inside the rifle, all of which play a part in the exterior
and terminal ballistics of the bullet.
The
expansion of the gas inside the cartridge is what drives the bullet
to its maximum velocity; the gas taking the path of least resistance
in the process of diffusion causes this velocity increase. With
regards to Newton’s first law the process can be summarized as the
bullet being the object at rest, and the expanding gas as the
unbalanced external force. As the unbalanced external force acts on
the bullet it pushes it out of the barrel. Another external force
acts on the bullet as it is pushed down the barrel; this second
force is the rifling, which produces the spin on the bullet and
causes a gyroscopic stabilization of the projectile. Though there
are other forces which act upon the bullet while in the rifle,
consideration of these two very important variables will suffice, as
they seem to be the most influential factors with regards to
exterior ballistics.
Now the
bullet is in motion and, according to Newton’s first law, the bullet
would stay in uniform motion unless acted upon by an external
unbalanced force. So what are some of these external unbalanced
forces? The most obvious is gravity; the other is air resistance, or
drag. These two forces are what cause a bullet to deviate from its
uniform path and they are the forces that constitute the study of
exterior ballistics. Gravity and resistance to air are the forces
that determine what requirements a ballistician must incorporate
into a bullet to try to achieve the best flight possible. These two
forces can be partially overcome by understanding Newton’s second
and third laws of motion.
Gravity
is a constant; it is a force acting on a bullet pulling it towards
the center of the earth at 32.0 feet per second squared. For
example, after one second of flight a bullet has fallen 16 ft
according to the constant force of gravity. It is an unbalanced
force in that it only acts in one direction, down. The only partial
solution to overcoming the effects of gravity is to increase
velocity, because the faster the bullet goes toward a target the
less time it has to be effected by gravity. Other than increased
velocity there is very little that can be done to minimize the
effects gravity has on a bullet.
The
bullets resistance to air is another force that acts to effect the
flight of the projectile. Its influence is much greater than the
influence of gravity, but the influence of air on a projectile can
be reduced to a much greater extent than the effect of gravity. The
general shape and design of our bullet are such as to optimally
reduce the drag created from the bullet cutting through the air. Air
can be considered an unbalanced force in that it acts on different
parts of a bullet to differing degrees, which unless properly
adjusted for can cause problems with stabilization. Most obviously
the drag caused by air acts on the front of the bullet as the bullet
pushes the air out its way. It also acts on the back of the bullet
when a vacuum is created from the bullet flying through the air. We
can apply Newton’s second law by saying a bullet is propelled toward
a target by overcoming all the forces that are acting on it, and the
more the effects of these forces can be minimized, the more optimal
the flight of the bullet will be.
Drag can
be understood in very simple terms by applying Newton’s third law of
motion. For every action there is an equal and opposite reaction, so
for every particle of air the bullet has to move out of its way that
particle of air exerts a force equal to its own mass and oppositely
directed to the path of the bullet. This is the concept of drag. So
it makes sense that at greater air pressure (more particle per space
of air) there will be more drag on the bullet. This same concept
applies to temperature (colder air is more dense), and to humidity
(greater humidity equals lesser density). So if we can minimize the
drag imparted by the bullet cutting through the air, the better it
will fly. The problem with this is being able to minimize drag at
high velocities, keeping the lethal potential of the bullet, and
having the bullet hold together under the pressure of all the forces
acting upon it.
Additional problems with drag are introduced as a bullet approaches
and surpasses the speed of sound. While at subsonic speeds a bullet
has minimal amounts of drag acting on it and it is relatively easy
to keep a stable accurate bullet at these low velocities. At
transonic speeds, which begin at about 800 fps, a shock wave begins
to form around the bullet as the air, which is being pushed aside,
must move at about the speed of sound, (1120fps), to get out of the
bullets way. The transonic speed that all bullets pass through when
accelerating and decelerating is the most unstable speed. It is an
inherently unstable speed because the bullet is beginning to form or
lose a shockwave. What this means is that the air around the bullet
cannot move out of the way fast enough, and so begins to pile up in
front of the bullet. This is what makes aerodynamics very important
in streamlining a bullet, and it is what makes it so difficult to
stabilize a bullet. This transonic stage of a bullets flight is
extremely turbulent and so it presents the largest problem for a
ballistician to overcome in creating an accurate bullet at long
distances. But, stabilizing a bullet with spin and increasing its
aerodynamic properties can overcome these problems.
At
transonic speeds a shockwave is beginning to form, as speed
increases to supersonic this shock wave grows. This means increased
drag from the shock wave requiring energy to be pushed along with
the bullet. However, supersonic speeds are much more stable than
transonic speeds, but the trick is getting a bullet through the
transonic stage and retaining its stability. The bullet must provide
the energy to push both itself and the shock waves produced in the
transonic and supersonic speeds through the air. This increased
energy required to propel both the bullet and the shock wave through
the air is another force which must be considered when understanding
the effects of drag on a bullet.
At high
velocities, under all these forces, many bullets will simply fall
apart, or vaporize. So in order to allow a bullet to hold together
there were limitations placed on what a bullet could do, and more
than anything else velocity was sacrificed. At Lost River Ballistic
Technologies we don’t believe in sacrificing velocity, because more
velocity means more energy transferred to the target, which means
more lethality. So we decided to make bullet’s that can hold up to
the intense forces put on them at high velocities. We have also
maximized our bullets resistance to the effects of drag by giving
the best shape and balance so as to streamline the bullet in flight.
With this new design we have decreased the effects of drag and
increased velocity. By increasing velocity we decrease the effects
of gravity with respect to distance traveled by the bullet and
increase lethality. By finding a way to reduce the effects of
gravity and air drag while increasing lethality we have come to
offer the best hunting bullet ever.
|
Information
Courtesy of:
Matthew
Mosdell
Lost
River Ballistic Technologies, Inc.
Post Office Box 801
Arco, Idaho 83213
Telephone: 1-888-807-8611
Local: 1-208-527-8611
Fax: 1-208-527-8613
Web URL:
www.LostRiverBallistic.com |
|
|
DRAG COEFFICIENT [Cd ]: A single variable used to characterize the
very complex dependence of the variables that characterize drag.
These dependant variables include the shape, inclination, velocity
squared, compressibility and air viscosity. In Gunnery and as Drag
Coefficient [ Cd ] relates to external ballistics, a higher Cd is
preferred for accuracy and bullet performance in flight.
Algebra Update: For those of us who have
fired a few boxes of ammo since our last algebra class, here is the
definition of COEFFICIENT.
co·ef·fi·cient:
- A number or symbol multiplied with a variable or
an unknown quantity in an algebraic term, as 4 in the term 4x, or
x in the term x(a + b).
- A numerical measure of a physical or chemical
property that is constant for a system under specified conditions such
as the coefficient of friction.
|
Drag coefficient
is proportional to { (gravitational force) / (inertial force) } and
is used in momentum transfer in general and free settling velocities
and resistance to flow calculations in particular.
It is normally
defined in the following form:
|
Where: |
|
g |
= |
Gravitational
acceleration |
|
L |
= |
Characteristic
dimension of object |
|
rho |
= |
Density of
object |
|
rho_f |
= |
Density of
surrounding fluid |
|
V |
= |
Velocity |
|
|
DRAM: Measure of weight equal to 27.34 grains. There are 16 drams
per ounce; 256 drams per pound.
DRAM EQUIVALENT: Term used
to indicate the approximate velocity of a shot charge by a comparison.
When shotgun shells were loaded with black powder, the powder charge was
measured in drams. Dram equivalents were originally developed in the
early 20th century to allow sportsmen an easy method of comparing the
‘new’ smokeless powder loads to the then more familiar black powder loads.
Used in connection with shotgun shells to describe how powerful they are,
by equating their power with an equivalently powerful black powder load.
The higher the number, the more powerful the shell is. Overall, the
most important thing to remember is that the higher the dram equivalent,
the higher the velocity for a given shot weight and, as a result, the more
powerful the charge. There are no real dram equivalents for loads that
didn't or couldn't exist in the black powder era. Key examples of
these are steel loads and some of the heavy magnum turkey loads.
|
WARNING: Dram equivalents values have no
relationship to the actual powder charge in a shell. These
values should never be used in determining smokeless powder charge
weights. There are no real dram equivalents for loads that
didn't exist in the black powder era. |
DRIFT: Deviation of a
projectile from the line of departure due to its' rotational spin or the
force of wind. 2. The sideways movement of the bullet in flight,
caused by the rifling. Note: The sight is usually designed to
provide an average compensation for drift at the usual range over the
firearms employment, but additional adjustment may be required for longer
ranges.
DRILL: The training of soldiers
in marching and the manual of arms. (as in Drill & Ceremonies) 2. An
implement with cutting edges or a pointed end for boring holes in hard
materials, usually by a rotating abrasion or repeated blows; a bit.
DRILL SIZE: Measurement of the
bit or cutting implement used to bore holes.
|
Drill Size to Decimal
Fraction Table |
Drill
Size |
Decimal
Fraction |
|
Drill
Size |
Decimal
Fraction |
|
Drill
Size |
Decimal
Fraction |
| 80 |
.0135 |
|
1/8 |
.1250 |
|
O |
.3160 |
| 79 |
.0145 |
|
30 |
.1285 |
|
P |
.3230 |
| 1/64 |
.0156 |
|
29 |
.1360 |
|
21/64 |
.3281 |
| 78 |
.0160 |
|
28 |
.1405 |
|
Q |
.3320 |
| 77 |
.0180 |
|
9/64 |
.1406 |
|
R |
.3390 |
| 76 |
.0200 |
|
27 |
.1440 |
|
11/32 |
.3438 |
| 75 |
.0210 |
|
26 |
.1470 |
|
S |
.3480 |
| 74 |
.0225 |
|
25 |
.1495 |
|
T |
.3580 |
| 73 |
.0240 |
|
24 |
.1520 |
|
23/64 |
.3594 |
| 72 |
.0250 |
|
23 |
.1540 |
|
U |
.3680 |
| 71 |
.0260 |
|
5/32 |
.1562 |
|
3/8 |
.3750 |
| 70 |
.0280 |
|
22 |
.1570 |
|
V |
.3770 |
| 69 |
.0292 |
|
21 |
.1590 |
|
W |
.3860 |
| 68 |
.0310 |
|
20 |
.1610 |
|
25/64 |
.3906 |
| 1/32 |
.0312 |
|
19 |
.1660 |
|
X |
.3970 |
| 67 |
.0320 |
|
18 |
.1695 |
|
Y |
.4040 |
| 66 |
.0330 |
|
11/64 |
.1719 |
|
13/32 |
.4062 |
| 65 |
.0350 |
|
17 |
.1730 |
|
Z |
.4130 |
| 64 |
.0360 |
|
16 |
.1770 |
|
27/64 |
.4219 |
| 63 |
.0370 |
|
15 |
.1800 |
|
7/16 |
.4375 |
| 62 |
.0380 |
|
14 |
.1820 |
|
29/64 |
.4531 |
| 61 |
.0390 |
|
13 |
.1850 |
|
15/32 |
.4688 |
| 60 |
.0400 |
|
3/16 |
.1875 |
|
31/64 |
.4844 |
| 59 |
.0410 |
|
12 |
.1890 |
|
1/2 |
.5000 |
| 58 |
.0420 |
|
11 |
.1910 |
|
33/64 |
.5156 |
| 57 |
.0430 |
|
10 |
.1935 |
|
17/32 |
.5312 |
| 56 |
.0465 |
|
9 |
.1960 |
|
35/64 |
.5469 |
| 3/64 |
.0469 |
|
8 |
.1990 |
|
9/16 |
.5625 |
| 55 |
.0520 |
|
7 |
.2010 |
|
37/64 |
.5781 |
| 54 |
.0550 |
|
13/64 |
.2031 |
|
19/32 |
.5938 |
| 53 |
.0595 |
|
6 |
.2040 |
|
39/64 |
.6094 |
| 1/16 |
.0625 |
|
5 |
.2055 |
|
5/8 |
.6250 |
| 52 |
.0635 |
|
4 |
.2090 |
|
41/64 |
.6406 |
| 51 |
.0670 |
|
3 |
.2130 |
|
21/32 |
.6562 |
| 50 |
.0700 |
|
7/32 |
.2188 |
|
43/64 |
.6719 |
| 49 |
.0730 |
|
2 |
.2210 |
|
11/16 |
.6875 |
| 48 |
.0760 |
|
1 |
.2280 |
|
45/64 |
.7031 |
| 5/64 |
.0781 |
|
A |
.2340 |
|
23/32 |
.7188 |
| 47 |
.0785 |
|
15/64 |
.2344 |
|
47/64 |
.7344 |
| 46 |
.0810 |
|
B |
.2380 |
|
3/4 |
.7500 |
| 45 |
.0820 |
|
C |
.2420 |
|
49/64 |
.7656 |
| 44 |
.0860 |
|
D |
.2460 |
|
25/32 |
.7812 |
| 43 |
.0890 |
|
1/4 |
.2500 |
|
51/64 |
.7969 |
| 42 |
.0935 |
|
E |
.2500 |
|
13/16 |
.8125 |
| 3/32 |
.0938 |
|
F |
.2570 |
|
53/64 |
.8281 |
| 41 |
.0960 |
|
G |
.2610 |
|
27/32 |
.8438 |
| 40 |
.0980 |
|
17/64 |
.2656 |
|
55/64 |
.8594 |
| 39 |
.0995 |
|
H |
.2660 |
|
7/8 |
.8750 |
| 38 |
.1015 |
|
I |
.2720 |
|
57/64 |
.8906 |
| 37 |
.1040 |
|
J |
.2770 |
|
29/32 |
.9062 |
| 36 |
.1065 |
|
K |
.2810 |
|
59/64 |
.9219 |
| 7/64 |
.1094 |
|
9/32 |
.2812 |
|
15/16 |
.9375 |
| 35 |
.1100 |
|
L |
.2900 |
|
61/64 |
.9531 |
| 34 |
.1110 |
|
M |
.2950 |
|
31/32 |
.9688 |
| 33 |
.1130 |
|
19/64 |
.2669 |
|
63/64 |
.9844 |
| 32 |
.1160 |
|
N |
.3020 |
|
1 |
1.000 |
| 31 |
.1200 |
|
5/16 |
.3125 |
|
|
|
DRILLING: German
for "triple", which is the designation for a three-barrel gun.
Drilling configurations typically consist of 2 shotgun or smooth bore
barrels and one rifle barrel.
DROP: The distance a bullet or projectile falls,
calculated from the line of departure.
DROP FREE: As in
Drop Fee Magazine. A drop free magazine is one that falls (assisted
only by gravity) when the magazine release is pressed. Drop
free magazines are generally considered desirable for speed reloads since
the shooter does not have to handle the empty magazine. They simply allow
the empty magazine to fall to the ground while reaching for the fresh
magazine.
|
