This is a guest post by my author friend, William R. Bartlett. It continues his discussion of all things firearms. Assault rifles have featured prominently in the horrific events in Florida, Las Vegas and elsewhere, so I wish to repeat that this series is only meant to help writers improve their writing and not to glorify weapons in any way. You can check out the rest of the series on firearms here. Today, Bill explains how rifles work and describes some common writing blunders. Enjoy and bookmark! 

A Writer’s Guide to Firearms by William R. Bartlett

Part 5: Shotguns


A shotgun is a long gun with a smooth bore, designed to hit either a moving target or a stationary target while using a less precise aim.

Shotgun Shells

Shotgun shots | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: The Guns and Gear Store

To understand a shotgun, one must first understand the shotgun shell.  Shotgun shells contain a propellant, or powder charge, encased in the brass cartridge base with a centerfire primer.  Attached to the brass is a plastic tube, that holds the wadding and the shot.  Originally, a cardboard pad that kept the powder charge from being distributed within the shot, the wadding is now a plastic cup with a crumple zone at the base that fits snugly over the powder.  The cup is filled with a number of round pellets, called shot, and the crumple zone is designed to minimize deformation caused by the jolt of the powder ignition, thereby allowing the shot to fly with minimal air resistance.  The wadding and shot are kept in place by a fold at the end of the

plastic tube, called a crimp.

The number of shot enclosed within the wadding cup varies by the size of the shot and the size of the shotgun bore.  The size of the shot is referred to by a number from 00 to 10.  Paradoxically, the smaller the number, the larger in diameter the shot with 00, commonly called ‘double aught’ as the largest, being nearly a quarter of an inch in diameter.  The larger shot is usually referred to as buckshot and can be used for hunting deer-sized animals in addition to being an anti-personnel load.  Smaller shot is called birdshot and is used for hunting small animals, birds and airborne targets, however even the smallest shot can be lethal to humans at close range.  Since larger shot have greater mass, they are more capable of resisting air density and traveling a longer distance.  Smaller shot don’t have as much mass and, consequently, a shorter range.


Shotgun shot | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: Winchester

While the vast majority of shotgun shooters choose to fire shot, there is an alternative.  Some shotgun shells contain a slug, a single large projectile.  In America, these are usually Foster slugs, are close to the bore diameter of the shotgun, and have a hollow base with the greatest mass in the nose.  Similar to a badminton shuttlecock, the forward weight keeps the slug flying true.  In addition, angled ribs on the outside of the slug impart a spin as rifling would do in handgun or rifle, offering still greater stability and range.  Other slug types exist, but, for purposes of brevity and just explaining the concept, we’ll confine our discussion to the Foster slug.  Slugs are used for hunting medium to large sized animals as well as in an anti-personnel role.


How Shotgun Shells Work

When the firing pin hits the primer, the primer releases a jet of hot gasses into the propellant, or powder charge.  This ignites the propellent and the consequent expanding gasses send the shot or slug down range.  A few feet out of the barrel, the wadding peels off and falls to the ground.  The shot continues toward the target, spreading and slowing as it travels farther from the weapon.  If the shooter is skilled, or simply lucky, some of the shot within the spread, or pattern, as it’s called, will intercept the target, breaking a ‘clay pigeon,’ the common name for a flying target, or either killing or disabling an animal.  Shooting a slug is similar to shooting a rifle, except that the wadding will also drop a few feet out of the muzzle and the range isn’t as great.

Shotgun Gauges

Shotgun components | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: shooting UK

The bore diameter determines the gauge of a shotgun with the smaller numbers resulting in larger bores.  This is because of the arcane process used to determine the bore size or gauge.  A shotgun gauge is calculated by the number of lead balls the size of the bore that will add up to one pound.  A twelve gauge shotgun will take twelve balls of the bore diameter to tip the scales at one pound.  Of course, there is an exception.  The smaller the number, the more projectiles can be fired with one shot, with one exception.  A four-ten shotgun doesn’t require four hundred, ten lead balls to add up to a pound.  Instead, a four-ten refers to the bore diameter in thousandths of an inch, or forty-one caliber, which is why it is written as .410 instead of being referred to as gauge, as in 12 gauge.  The largest bore shotgun in mass production in America is the 10 gauge, but the most popular size is a 12 gauge.  In addition, there is also a 16 gauge, a 20 gauge, and a 28 gauge along with the .410 that I just mentioned.


Like a rifle, shotguns have a barrel, a firing mechanism with a trigger, a forearm and a buttstock.  Some thirty years ago or more, these were all wood, usually a European walnut, but polymer acrylics are very popular these days for durability and ease of maintenance.

Shotgun parts | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: how stuff works

Shotgun barrels have a unique feature called ‘choke.’  This is a constriction inside the barrel that shapes the pattern for range.  The four main chokes in use in America today are ‘cylinder,’ ‘improved cylinder,’ ‘modified,’ and ‘full’ choke.  A cylinder or open cylinder choke, as it’s sometimes called, has no choke and shoots as if there was no barrel past the chamber.  This is used when the target is at an extremely short range.  An improved cylinder choke is a slight choke and is also used for short range shooting, but maintains a pattern a little farther than the open cylinder choke.  Both of these chokes are useful when shooting quail because they can and do fly out from underfoot.  A modified choke is useful when shooting smaller targets at longer ranges, such as dove.  A full choke constricts the pattern the most and is useful for shooting birds at longer ranges, like ducks, geese, and turkey.

There are three main types of shotguns and they are separated by the way they work, called an action.  These three types are a break action, a pump action, and a semi-automatic, frequently called an autoloader.  Since most shotguns are used for moving targets, a quick follow-up shot is helpful.  The fastest type for a second shot is a double-barreled break-action shotgun.  The next fastest would be the semi-automatic, with the pump action being the slowest.  However, pump action and semi-automatic shotguns can be in battery for an additional shot almost as soon as the shooter recovers from the recoil of the first thought, rendering the differences moot.

Break Action Shotguns

How a Break Action Shotgun Works


Shotgun | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: Pixabay

The shooter unlocks the shotgun either by pressing a button or by pushing a lever to one side.  Once unlocked, the weight of the barrel causes the breech, or rear of the barrel where the chamber is exposed, to rise.  The spent shell either rises for ease of extraction or is automatically ejected.  A new shell(s) is inserted by hand into the chamber(s) and the forearm is raised to bring the weapon into battery.


Almost all modern, break-action shotguns have an internal firing mechanism that cocks, either on opening or on closing.  Older shotguns and reproductions of older shotguns have an external hammer or two, with double-barrel shotguns having two.  Many break-action shotguns have more multiple barrels with two being the most common by far.  Some multi-barreled shotguns have the barrels stacked, one on top of the other, and are referred to as an ‘over-and-under.’  Others multi-barreled shotguns are arranged with one barrel beside the other and are called a ‘side-by-side.’  Many have different chokes in different barrels, one side being more open than the other.  Some multi-barreled shotguns have a separate trigger for each barrel, which allows both barrels to be fired at the same time.  Other multi-barreled shotguns have one trigger for both barrels, with some selector mechanism that allows the shooter to choose which barrel is to be shot first.  After firing the first shot, the shotgun automatically switches to the other barrel, placing it in battery.

Because of the imprecise nature of most shotgun ammunition, the weapon is seldom aimed.  Rather, one points a shotgun, keeping both eyes open taking advantage of humanity’s natural binocular vision to judge the distance to the moving target.  The exception would be a shotgun primarily equipped to shoot slugs, which would be aimed like a rifle.

Operation of a Break-Action Shotgun

This is one of the most simple of firearms to operate.  All the shooter has to do is break the action by pressing a small lever or button, thereby exposing the breech with the empty chamber(s), insert the ammunition, close the action, and pull the trigger(s).  Most modern break action shotguns have a manually-operated mechanical safety, but some classic models may not.  Double barreled shotguns either have two triggers, one for each barrel, or a single, selective trigger, where one can choose the barrel to be shot with a simple, manual action.  Most shotguns with a single, selective trigger have an internal, mechanical device that automatically selects the unfired barrel after a shot is fired.


As stated above, break action shotguns are extremely simple to use.  In addition, they can be very safe to carry with the breech open.  Anyone within eyesight can readily verify that the weapon is in a safe mode because A) the weapon cannot function with the action open, and B) anyone can verify that the chamber is open and the weapon is not loaded.  Multi-barreled shotguns are extremely fast for a follow-up shot and, if equipped with dual triggers, both barrels can be fired at the same time.  Some break-action shotguns have ejectors that will remove the spent shell, facilitating manual reloading.  Break-action shotguns are quickly disassembled for cleaning.  Usually, this involves only the removal of the forearm followed by lifting the barrel off the frame, but can be as simple as breaking open the shotgun and cleaning the barrel.


With a single barrel, break-action shotgun, the spent shell must be manually extracted after each shot and it must be manually reloaded.  This makes follow-up shots virtually impossible.  After both shots are expended on a double-barreled shotgun, both spent shells must be extracted and new ones loaded by hand.  Double-barreled shotguns, whether over-and-under or side-by-side, tend to be more expensive than pump or semi-automatic shotguns.  Just the forging of two barrels and joining them together results in a higher price.  When one includes fine tooling in the frame and hand crafting on the stock, prices can easily exceed a thousand dollars.  Recoil can be especially noticeable in a break action shotgun.  Heavier loads with heavier powder charges can result in an uncomfortable jolt to the shoulder, especially in a single barreled shotgun that has no extra weight to absorb some of the recoil.

Pump Action Shotguns

Operation of a Pump Action Shotgun

Moosberg pump action shotgun-DICK'S Sporting Goods | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: DICK’S Sporting Goods

Pump action shotguns are probably the most popular style in America.  A tubular magazine below the barrel holds three to five shotguns shells in sporting shotguns and up to seven or eight shells in a tactical model.  Many states have restrictions on magazine capacity for sporting use and require a plug or some other device when the shotgun is used during hunting.  Just like a pump action rifle, the forearm is detached from the butt stock, separated by the receiver.  Pulling the forearm back ejects the spent shell and pushing the forearm forward chambers a new one.  The shells are inserted into the magazine at the bottom of the receiver.   Another shell can be inserted into the chamber if the action is open.  Virtually all pump action shotguns have a manually-operated mechanical safety and an internal hammer.  Ironically, pump action shotguns have a history of military use, while pump action rifles have none.

Advantages of a Pump Action Shotgun

Follow-up shots are very quick because the action of ejecting a spent shell and chambering a new shell can be combined with both the recoil and the recovery from the recoil.  Pump action shotguns were developed in the late 19th century, so the design is tough, durable, and proven by well over a century of use.  Because of the tubular magazine below the barrel, a pump action shotgun can have the magazine replenished while keeping the weapon in battery.  The popularity of this style of shotgun is reflected in the pricing.  A pump shotgun is among the better values, although presentation grades with stocks of hand-checkered wood and receivers with floral engraving, and, sometimes, gold inlays, can be very expensive.  Some cite the sound of cycling the action of a pump shotgun as a criminal deterrent.  The metallic clicks involved allow a criminal to know that a lethal weapon is present and in battery.

Disadvantages of a Pump Action Shotgun

As with a break action shotgun, recoil is noticeable and can be painful, especially when using heavier loads of both propellant and shot.  The weight of the receiver and action can absorb some of the recoil, but heavier loads can be punishing.  A thorough cleaning requires barrel removal.  Unlike a break action shotgun where one need only open the action to clean the barrel, a pump shotgun must have the barrel removed for proper cleaning after use.  Although barrel removal and reinstallation is typically a simple process, it is more time-consuming than cleaning a break action shotgun.  Some discount the value of simply cycling the action of a pump shotgun as a deterrent.  In order for the criminal to hear the sound, they must be close to the shooter, possibly too close for a long gun to be of value.

Semi-Automatic Shotguns

Operation of a Semi-Automatic Shotgun

srm-M1216 | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Image: Impact Guns

As with a semi-automatic rifle or pistol, this type of shotgun fires one shot for each pull of the trigger.  Most sporting shotguns have a tubular magazine under the barrel, similar to that of a pump action shotgun.  Tactical semi-automatic shotguns can have a removable, box-style magazine, similar to that of an AR-15, or they can have a tubular magazine.  Loading the tubular magazine of an autoloader is similar to loading the tubular magazine of a pump.  Simply insert a shell into the magazine through a well in the bottom of the receiver.  Laws regarding magazine capacity for hunting also apply to semi-automatic shotguns.  Most semi-automatic shotguns are gas operated.  They have holes about midway down the barrel that siphon off some of the expanding gasses from the powder ignition after pressures within the barrel have dropped to safe levels.  These gasses are redirected toward the breech of the weapon where their energy is used to shove the bolt rearward and extract the fired cartridge.  This action compresses a spring and, when the gas pressure drops, the spring forces the bolt forward where it chambers another shotgun shell, placing the weapon into battery.  Virtually all semi-automatic shotguns have a manually-operated mechanical safety.

Advantages of a Semi-Automatic Shotgun

The main advantage is ease of use.  Simply shoulder the weapon and pull the trigger.  This makes for fast follow-up shots, particularly when hunting game birds.  The action and additional weight absorbs some of the recoil, making them more comfortable to shoot.  Like a pump shotgun with a tubular magazine, the semi-automatic can have the magazine reloaded, or topped off, as it’s sometimes called, while the weapon is in battery.

Disadvantages of a Semi-Automatic Shotgun

Because the action cycles so quickly, ammunition can be extended rapidly.  Frequently, the shooter can take a second or third shot that may have been better not taken.  By this time, the range has increased, decreasing the chances for a clean kill and increasing the chances for a crippling shot.  The complexity of a semi-automatic shotgun increases the possibility of a malfunction.  The additional parts also add weight, which can increase the weariness of the shooter.  Cleaning a semi-automatic shotgun is complicated, even more so than cleaning a pump shotgun.  The barrel and forearm must be removed because powder residue can foul the action and prevent proper operation.  All traces of powder fouling must be removed after a shooting session, which can take some time.

Writing failures

Here are some common writing failures for shotguns:

  • A quick follow-up shot with a single barrel, break-action shotgun.  As stated above, the process involved in reloading is lengthy.
  • Failure to insert a shell into the chamber.
  • Failure to reload.  Even though a magazine can hold several cartridges, it can still be depleted.
  • Sighting on a target.  Most shotguns are made to be pointed, not aimed.  Most don’t even have a rear sight, something necessary for proper aiming.  The only sight on most shotguns is a bead at the top, center of the barrel.  Some beads have fiber optics in a color that is easily noticeable.
  • Failure to account for the noise.  The sound of the gunshot can result in hearing damage if fired within closed spaces.
  • Failure to account for the safety in the proper manner.  When one hears a click after pulling the trigger, one hears an attempt to fire the weapon without a round in the chamber.  The click is the hammer hitting the firing pin.  However, the safety blocks the trigger’s rearward motion, making a click impossible.  No trigger motion, no click.  Squeezing the trigger with the safety on makes no noise.  None.
  • Hitting a target at long distances.  Even a low-powered round, like a .22 rimfire, can travel up to a mile.  Shotguns, however, are made for close range use and most shot travels less than three hundred yards.  Shotgun slugs are designed to shoot accurately at about fifty to seventy-five yards or so and usually travel less than three hundred yards.


Some shotguns are bolt action.  These are seldom used for two reasons.  Firstly, the legendary accuracy of bolt action rifles isn’t necessary for a shotgun, where most projectiles emerge from the barrel as a swarm of shot.  Secondly, shotguns are designed for quick follow-up shots.  Cycling a bolt takes too much time for an effective second shot.  Bolt action shotguns should be viewed as a single shot shotgun where additional ammunition is carried inside the weapon.  Although, the most popular type of multi-barreled shotgun is the double barrel, there are shotguns with three or even four barrels.  Some shotguns are paired with a rifle barrel, typically, but not always, on top of the shotgun barrel.  The extra barrels add weight and cost more than the double-barreled shotguns.

I hope this helps with your writing.  The next, and last, installment will give a general background of weapons and techniques used prior to the development of brass cartridges.