Friday, October 29, 2010


One of the things I’ve seen the most in writer’s forums is confusion about the type of gun vs. the type of round.  I’d like to hit that part first.

A 9mm Parabellum has no idea whether it’s begin fired from a Glock, a single shot Contender, or an MP5 submachine gun.  When people ask for a powerful handgun, someone almost always bring up a Glock, but never mentions the caliber.  This is a danger sign.  Don’t listen to these people.

There is no real difference in power between the Desert Eagle in .44 magnum and the Smith and Wesson revolver Dirty Harry used to teach basic math in 1971.  If they have the same powder charge and the same bullet, they will have basically the same effects.

So, what does “caliber” mean?


I touched briefly on what revolvers were.  Now I’m going to dig into them in detail.
Single action revolvers require that the hammer be pulled back by hand in order to cock them.  This can make them much more accurate than a double action, because far less effort is expended to pull the trigger.  On the other hand, they are slower.  The rate of fire isn’t any slower, really, but the reloading time is.
To reload a single action revolver, you open a little gate at the back of the gun.  This is found just below and to one side of the hammer.  It will allow you to see into one chamber at a time.  On the front of the cylinder, under the barrel is a small rod on a spring.  You use this to force the spent casing out of the chamber.
Once the empty is out, a new round can be loaded.  This has to be done for each chamber.  Once all six have been reloaded, the gun is ready for use.

Thursday, October 28, 2010

Slow Motion Look at Recoil

Let’s take a look inside a gun as it goes off.  For the purposes of this, we’ll use the simple Blowback action of a Sig 230/232.   It uses a .380 ACP, otherwise known as a 9x17mm, or 9mm kurtz.

First we slide a loaded magazine into the grip of the pistol. 
Once the magazine is in place, we pull back on the slide.  This has the single effect of cocking the hammer.

Now, we release the slide.  The spring around the barrel will push the slide back into place.  As it moves forward, the slide will strip one round off the top of the magazine and slide it into the chamber.  The spring also holds the breech face, which is part of the slide, against the back of the casing.  The weapon is loaded and ready to fire.

Actions and Reactions

When people talk of guns, they often refer to them by the action the gun uses to prepare the next round to fire.

For centuries, all guns were single shot weapons.  You’d fire once and then have to reload.  If you wanted to fire more than once, you needed to add another barrel.

Until the metal cartridge came along, all guns were muzzle loaders.  That means that the powder and bullet were shoved down the front of the barrel.  The “primer” may have been a piece of flint, or a burning string that the shooter placed in the flash hole by hand, or it may be a modern percussion cap that ignites the charge.  These guns are still called by the method of ignition used: Matchlock, Flintlock, Cap and Ball, and so on.

Other types of single shot actions are:

Parts and Names of Parts

Before we can get into the different types of guns and how they work, we need a list of common terms.

A fully loaded Cartridge consists of four things.  The Bullet is the part that flies out of the front and does the damage.  The Powder is what burns to make that happen.  The Primer starts the powder burning, and the Shell or Casing holds it all together.

Shell casings come in two basic types and two basic configurations.  Handguns tend to use straight wall cases.  This means they are about the same diameter at the top as they are at the bottom.  Rifles tend to use a bottle shape where the neck of the case is just big enough to hold the bullet, while the bottom of the case is much larger.  This allows them to hold more powder, and increases the power of the round.

The other two differences relate to the Rim of the case.  The rim can either stick out slightly, like a small, stubby L, or it can be recessed in so the diameter of the rim is the same as the diameter of the case.  This is the best indicator of whether or not the case was intended for use in a vertically stacked magazine, as used in most modern semi automatic actions for both rifles and pistols.  Recessed rims are called Rimless cases.

Collectively, all of this is called a cartridge, or Round.  It is also sometimes called a bullet, though that is technically the name for just the bit that flies out.  The Bullet can also be called a Slug, though that is an outdated term unless dealing with a shotgun that fires a single projectile.

Firearm Basics

This section came about as a result of the sheer number of times I answered these types of questions on several different forums.  Rather than re-write it every time it comes up in the future, I figured I’d post it for general viewing.

So, what is this?
This is basic information about firearms which is aimed (the information, not the firearms) at writers who want to get things right.  If you are a writer, or just have an interest in the basics of how firearms work, I encourage you to look around.  If you already know this stuff, and want to fact check me, I welcome that as well.

General Overview

Hi there.

This section is intended to be a resource for fiction writers who want to include firearms in their work, but know next to nothing about them.  It started because of some questions on the National Novel Writing Month (NaNoWriMo) boards.  People would ask questions about something and end up getting a lot of contradictory information.  Rather than re-write it all every time it comes up, I thought I’d put it out this way.
If you looked here you probably one of three types of people.