Version: December, 1993
Table of Contents:
1 Introduction
1.1 Purpose
The document introduces some very fundamental ideas and terminology
regarding guns, particularly handguns, to beginners. If you know
next-to-nothing about guns, read it straight through.
1.2 Gun Safety
The very first information covered with people new to guns is that of
gun safety. The basic rules are:
* treat every gun is if it were loaded
* always point the gun away from people
* keep your finger away from the trigger until you are ready to fire
* keep the action open (un-fireable) until ready to shoot
Complete safety rules are available everywhere.
1.3 Scope
This is nothing more than a primer (pun intended); find yourself a
knowledgable mentor as you continue to get educated about this topic.
My hope is that Handgun Basics will make the rest of your journey a
little smoother. Besides all the definitions and explanations, I have
included some digressions to provide factual information and help
dispel much of the misinformation already out there, such as the
"plastic" gun.
2 The Basics of Guns and Ammunition
2.1 General Introduction
2.1.1 What is a handgun?
Webster: "gun: noun. a weapon consisting of a tube of metal,
fixed in a stock or mounted on a carriage, from which projectiles
are fired by the force of an explosive, usually gunpowder... a
cannon, rifle, revolver or pistol"
A handgun is a gun designed to be held and fired with only one
hand. In practice, the other hand is also used underneath for
greater support.
2.1.2 Origins
The need that men were attempting to fulfill when they invented
the gun was that of a better tool for combat. What made it
better was that it could be used from a remarkably far distance,
had devastating stopping power, was easy to build & maintain, and
every man could learn to use it and carry several of them with
ease.
Today, the handgun is still part of standard law enforcement
apparel. Millions of ordinary citizens also possess guns, a
right which our Founding Fathers included in the Constitution.
The 2nd Amendment in the Bill of Rights states that "...the right
of the people to keep and bear arms shall not be infringed..."
2.1.3 How ammunition works
To understand what a gun does, you must first know what makes the
projectile it fires do that. The projectile is called a bullet.
The object you load into the gun is called a cartridge, or a live
round of ammunition. To be fired, the cartridge must be in the
chamber of the gun. It is a misnomer to call the cartridge a
bullet; the bullet is only the part that strikes the target.
All cartridges consist of a casing containing powder and capped
with a bullet, and a means of detonating the powder. There are
many different constructs. For example, a center-fire cartridge
has its detonator, called a primer, pressed into the center of a
small hole in the base of the casing. A rim-fire cartridge has
its detonator lieing inside the casing's bottom rim.
When the gun is triggered to fire, the following sequence of
events occur. A firing pin strikes the detonator (henceforth
called the primer), which then explodes. This explosion is very
small, but it does ignite the powder inside the casing. When the
powder ignites, it causes a very large increase in pressure
within the casing, which blows the bullet out fast. This last
step comes from Newton's Third law, "for every action, there is
an equal an opposite reaction". The shooter must hold the gun
only firmly enough to absorb the reactive force, called recoil,
propelling the gun towards him. The recoil requires some getting
used to, but using a death-grip is neither neccessary nor
advised.
The explosion is contained within the chamber of the gun, and
only heavy metallic materials can withstand such a blast. There
is absolutely no such thing as a gun made entirely of, or even
mostly of, plastic. We are many, many years away from non-
metallic technologies capable of containing such explosive
forces. Today's metal-detectors, however, are sensitive enough
to detect something as small as a hairpin.
2.1.4 General construction of guns
Now then, the gun is therefore serving several purposes. It is
the containment device for the entire process. It has a
triggering mechanism that causes the firing pin to strike the
primer. It has a tube of metal called a barrel that directs the
bullet in a specific direction. After you fire the bullet, what
happens next depends on what type of gun you have.
Guns also have appendages on them called sights that enable the
shooter to aim the gun to strike a particular target. In the
movies, actors usually just hold their gun at hip-level, point it
in the general direction of a person several yards away, shoot
and hit their target. That, of course, is fiction. The key to
hitting any target is learning to use the sights properly, and it
takes lots of practice.
Handguns have a grip that makes them easy to hold in one hand
while firing. In revolvers, the grip is usually solid. A semi-
automatic grip is hollow since it contains the magazine which
contains more cartridges. These terms are defined below.
Squeezing the trigger of an empty gun is known as dry-firing. On
some guns, particularly rim-fire types, doing this repeatedly can
damage the firing pin, which should be avoided.
2.2 Types of handguns
Guns can be classified in many different ways, such as:
* By loading technique: revolvers and auto-loaders
* By modes: single-action (SA), double-action (DA), both (SA/DA)
* By ammunition: 22 caliber, 9mm, 45, .380, rubber, ...
* By purpose: self-defense, competition/recreation, combat,
hunting, collecting...
* By material: wood frame, blued or parkerized finish, stainless...
* By price range: up to $300, $500, $1000, $3000, $5000...
Both revolvers and semi-autos can accommodate a variety of types and
sizes of ammunition. Semi-automatics are a type of auto-loading
pistol. Auto-loading means that after a shot is fired, the spent
casing is automaticaly ejected and the new round is loaded into the
chamber. Revolvers cannot auto-load. A basic understanding of the
construction of different guns is needed to understand what these all
terms mean.
2.2.1 Revolvers
After flintlocks, the first modern handguns invented were
revolvers. In a revolver, the cartridges are placed inside the
perimeter of a revolving cylinder. As the cylinder turns, each
cartridge is placed inline with the firing pin and the barrel so
it can be fired. Immediately after the bullet is fired, nothing
else happens. The cylinder must be turned to line up the next
cartridge before the gun can be fired again. The spent casings
remain inside until they are manually removed. Typically, a
revolver has a capacity of 5 or 6 cartridges. The cartridges can
be placed inside the revolver one at a time, or a metal retaining
clip that holds a round of cartridges can be used to insert all
of them at once.
Now assume a live round is in the chamber and is fired. The
firing pin is struck by a spring-loaded hammer. The hammer must
first be pulled back (cocked) so that when it is released, the
force of the spring will cause the hammer to strike the pin with
enough energy to detonate the primer. To summarize, the two
actions that must take place are:
(1) cock the hammer,
(2) release the hammer into the firing pin (the hammer
strikes the firing pin).
2.2.1.1.
When we speak of a gun having single-action (SA) or double-action
(DA) we are refering to what is happening while the trigger is
being squeezed. When the trigger of a gun in SA mode is
squeezed, only (2) happens. When the trigger of a gun in DA mode
is squeezed, both (1) and (2) happen. Both revolvers and auto-
loaders are available in SA-only, DA-only and SA/DA mode, but
remember, no revolver can auto-load.
2.2.1.2 Revolvers in single-action mode
If a revolver is in SA mode, then the hammer has already
been manually cocked. When the trigger is squeezed, only a
single action will take place, namely the hammer is
released. After a round is fired, the revolver goes back
into DA mode. Trigger-squeeze force is typically very light
under this circumstance. Only guns with extraordinarily
sensitive triggers are termed "hair-trigger". Usually, the
most accurate shooting possible is performed in SA mode.
Revolvers that only work in SA mode, termed SA-only, always
require manual cocking in the form of pulling back the
hammer with a thumb or the other hand, and are therefore
totally impractical for combat or self-defense. They are
used for competitive target-shooting and hunting. When
cocking the hammer, the cylinder will be also be turned.
Examples of SA-only guns:
2.2.1.3 Revolvers in double-action mode
If a revolver is in DA mode, then the hammer is not
initially cocked. Two actions must take place as the
trigger is squeezed to fire the gun. The first half-inch or
so of trigger-pull will both cock the hammer and rotate the
cylinder. The final moment of trigger-pull results in the
hammer being released. Trigger-squeeze force is naturally
greater than that of SA mode. Shooting accurately is
somewhat more demanding because of the additional physical
effort of cocking the hammer during the trigger squeeze.
A DA-only revolver has a concealed (not-exposed) hammer.
Such revolvers are popular self-defense weapons because they
are always uncocked until fired, and the concealed hammer
means there's less chance of it getting snagged on something
when it's hurriedly pulled from a purse or pocket.
2.2.1.4 Revolvers in single-action and double-action mode
If a revolver is capable of SA/DA mode, then it can be
operated in either of the above ways. All revolvers always
go back to DA mode immediatly after a shot has been fired.
Revolvers do not have external manual safeties, so they
should only be put into SA mode when preparing to fire.
A revolver in SA mode can also be decocked manually. The
safe way to do this is to use the cylinder-release to clear
the cylinder away from the firing pin path, point the gun in
a safe direction and squeeze the trigger to dry-fire the
weapon. The dangerous way to do this is to press and hold
the cocked hammer down with your thumb, point the gun in a
safe direction, squeeze the trigger and gradually ease the
hammer into decocked position with your thumb. If you let
go of the hammer accidently you might fire the gun.
2.2.1.5 Reloading
The revolver is not an auto-loader. That means the next
cartridge is loaded into place (ie. the cylinder is turned a
few degrees) when the hammer is being cocked, which may be
accomplished manually or while triggering from DA mode, as
explained above.
Reloading a revolver is a two-step process. First the spent
casings must be removed, and second the new cartidges must
be put in.
2.2.1.6 Miscellaneous
The first revolvers made were SA devices, as the designers
had not yet figured out how to connect the triggering
mechanism to control the hammer and turn the cylinder. In
movies about the old west you sometimes see the shooter
pulling back the hammer with his thumb before firing; it had
to be done manually. If he wanted to fire several rounds
quickly, he used his other hand to rapidly cock back the
hammer, fire, cock, fire, and so on.
All revolvers are kept decocked for safety. A revolver in
SA mode is in a more precarious state since the trigger need
only be squeezed a fraction of an inch to fire (it's already
cocked), and there is no manual safety. Hunters and
competition-shooters put their revolver into SA mode just
before they prepare to shoot to increase their accuracy. If
a revolver is fired first in SA and second in DA mode, the
trigger-squeeze force is inconsistent.
2.2.2 Semi-automatics (auto-loaders)
A semi-auto handgun fires a bullet the same way as a revolver
does. The difference lies in what happens after the bullet has
been fired. After a semi-auto fires a bullet, it utilizes an
internal spring to conserve some of the explosive energy to do a
few other things automaticly. All semi-autos will eject the
spent casing (so it is wise to wear eye protection) and insert
the next round from the magazine into the chamber. No revolver
can do that. If the semi-auto is not DA-only, it will also re-
cock the hammer automatically. The operator must let go of the
trigger and then squeeze it again to fire the next round.
Semi-autos are constructed very differently from revolvers in
order to accomplish all this. The capacity of a semi-auto is
limited only by the capacity of the magazine feeding it "plus
one" round in the chamber. The typical quantity is 5 to 17
cartridges in a magazine. The cartridges are packed into a
spring-loaded magazine which slides into the grip of the gun.
A fully-automatic gun, also known as a machine gun or an assault
rifle, does everything a semi-auto does except that the operator
need not let go of the trigger and squeeze to fire again. As
long as the trigger is depressed, the cartridges continue to be
fed and fired in bursts or continuously. Examples of full-autos:
M16, M60, UZI
2.2.2.1 Semi-auto in single-action mode
If a semi-auto is SA-only, then it also has a manual safety
switch that prevents the trigger from functioning until the
safety is manually switched OFF by the operator with a flick
of the thumb. Such a handgun is usually kept "locked and
cocked", meaning that it must be manually de-locked (ie.
turn off the safety) and then be triggered to fire. It
would be foolish to carry an SA-only handgun with the safety
OFF.
The SA-only semi-auto is a popular self-defense weapon
because of the speed and light trigger force of SA firing,
and the preventive step of having to turn off the manual
safety before it can be fired.
The manual safeties are extremely reliable, but many people
don't feel comfortable carrying a cocked gun, so more styles
came along, as described below. The difference between the
SA-only semi-auto and the SA-only revolver is that the SA-
only semi-auto is always automatically cocked, while the SA-
only revolver requires manual cocking and has no manual
safety. Example of SA-only semi-autos: Ruger Mark II, all
Colt 1911 variants
2.2.2.2 Semi-automatics in double-action mode
If a semi-auto is DA-only, then it is identical to a
decocked revolver in terms of readiness to fire. A DA-only
semi-auto has no manual safety. The only automatic process
that a DA-only semi-auto undergoes is that of the next
cartridge being loading into the chamber once the previous
one is ejected.
The DA-only semi-auto is a popular self-defense weapon
because it is always decocked, and the operator doesn't have
to worry about remembering to turn off a manual safety
(there isn't one). Notice these conflicting rationales
indicate that not everyone feels the same way about the
security of SA mode or the practicality of manual safeties;
it all depends on your individual tastes and preferences.
2.2.2.3 Semi-automatics in single-action and double-action mode
The SA/DA semi-auto is the answer if you want an SA gun
without a manual safety. It has a decocking lever that
allows you to safely decock the hammer from SA to DA with
the flick of a switch. Therefore only the first shot is in
DA mode, and all subsequent shots are SA because the gun
always goes into SA mode after it's fired. The only
disadvantage to this system is that there is an inconsistent
trigger-squeeze: the first pull is a little stiffer than the
others.
2.2.2.4 Other-action modes
Some DA-only semi-autos are actually "action and a half" or
"safe action", meaning that as much as one-quarter of the
cocking has been achieved automatically, and the operator is
really only supplying three-quarters of the remaining force
to cock and shoot, and not the entire double action force.
This does not jeopardize safety because, in case of a
critical mechanical failure, one-quarter cocking force is
insufficient to detonate the primer. Example of semi-DA-
only semi-auto: Glock
Some SA-only semi-autos are "squeeze-cocked". These are
cocked only when the operator grasps the grip of the gun,
thereby depressing a lever that cocks the gun. If the gun
is not being held, it is decocked. Some considered this a
"best of both worlds" gun, since it is always decocked when
not being held, requiring no manual safeties, and goes into
SA mode when held, with consistent trigger squeeze force.
Example: HK
2.2.2.5 Miscellaneous
The DA-only and SA-and-DA semi-autos are increasingly
popular since they offer the main advantage of the
revolvers, namely DA mode. The advantages to semi-autos are
greater cartridge capacity, faster magazine-changing, and
more compactness. The disadvantage to semi-autos used to be
that they were considered more hazardous since they were
always in SA mode, but this is no longer the only choice.
Law-enforcement personnel carry both revolvers and semi-
autos depending on their individual preference. Semi-autos
were once considered less dependable since they were more
likely to jam than revolvers, but modern technology has
improved semi-autos to the point that that hardly ever
happens. All guns should be cleaned well regularly to
ensure their proper operation.