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 4 (cont’d): Assault Rifles

Operation of Semi-Automatic (“Assault”) Rifles

AK-47 components | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

AK-47 components. Source: PyramidAir

First, I want to discuss the elephant in the room, assault rifles, or assault weapons. The Germans developed the first assault rifle during WWII, the MP-43. It featured an intermediate cartridge, that is, one that is stronger than the pistol ammunition used in submachine guns, but not as strong as the cartridge used in their Mauser rifles. It had a recognizable pistol grip, was effective to three hundred meters, and had a detachable box magazine, capable of holding thirty rounds. A key component was a selector switch that allowed the choice of semi-automatic fire, one shot per trigger pull, or fully automatic fire, more than one shot per trigger pull. Adolph Hitler reportedly named the weapon ‘Sturmgewehr,’ (pronounced SHTURM-guh-vair) which translates to ‘assault rifle,’ although some sources dispute Hitler’s direct involvement. The weapon was subsequently given the official name of Sturmgewehr-44, or StG-44 and was used by the Germans throughout the remainder of the war. Both the Russian Automat Kalashnikov-47, or AK-47, (which bears a strong resemblance to the StG-44) and the American M-16 share the characteristics of the first assault rifle: an intermediate cartridge, detachable, high-capacity box magazine, an identifiable pistol grip, an effective range of at least three hundred meters, and a selector switch that toggles between fully automatic and semi-automatic fire.

The first definition of assault rifle in my online dictionary specified the ability fire at both automatic and semi-automatic rates of fire. The second definition in the same online dictionary states that an assault rifle is a non-military weapon that looks like a military weapon but fires in a semi-automatic mode only. The United States Congress has defined an assault weapon as being a semi-automatic rifle with a detachable box magazine, a pistol grip, and, possibly, other features such as a barrel shroud or a flash suppressor. Clearly, the term, assault rifle, or assault weapon, has evolved from the original definition that specified fully automatic fire capability to include rifles that resemble military weapons, but are functionally identical to other civilian semi-automatic rifles.

All semi-automatic rifles are magazine fed, either with a fixed, tubular magazine under the barrel or with a magazine, fixed or removable, under the action. When the trigger is pulled, an internal hammer strikes the firing pin, driving it into the cartridge primer and igniting the powder, propelling the bullet downrange. The bolt cycles rearward, extracting and ejecting the spent cartridge. When the bolt has reached maximum rearward travel, a compressed spring forces the bolt forward, stripping a fresh cartridge from the magazine and driving it into the chamber, placing the weapon into battery. When the last cartridge in the magazine has been fired, the bolt stays open near the maximum position of rearward travel.

Like semi-automatic handguns, most semi-automatic rifles that shoot pistol ammunition operate on a blowback principle where a spring holds the bolt against the bullet in the chamber. When the pressure in the barrel has dropped to safe levels, the bolt moves backwards and ejects the spent cartridge. The compressed spring then forces the bolt forward, stripping a bullet out of the magazine, and feeding it into the chamber as the weapon resumes battery.

Rifles firing a high-powered cartridge operate on a slightly different principle. Instead of relying on spring compression to keep the bolt closed, the bolt has locking lugs that engage when the weapon is in battery. When the rifle is fired, expanding gasses are siphoned off before the bullet leaves the barrel. These gasses are channeled rearward where the pressure pushes the bolt backwards, disengaging the locking lugs in the process. By this time, the bullet has left the barrel and pressures have dropped to safe levels. The bolt travels rearwards, extracting, and ejecting the spent cartridge in the process. When the bolt has reached the maximum point of rearward motion, a spring forces it forward. During forward motion, the bolt strips another cartridge from the magazine and pushes it into the chamber, engaging the locking lugs in the process, but doesn’t fire the new round. The final act of placing the weapon into battery is to relax pressure on the trigger. In a semi-automatic rifle, this must happen before the weapon can be fired again. One trigger squeeze equals one shot. The cycling of the action happens almost too quickly for the eye to notice. Usually, movement of the bolt is only a blur while the empty brass flies away from the weapon. As with other semi-automatic weapons, the bolt stays open once the last round in the magazine has been fired. The empty magazine is ejected and a loaded magazine is inserted into the magazine well. The bolt release is pressed and the bolt slams home, inserting a cartridge into the chamber during the process. If the bolt is closed on an empty chamber, the action must be cycled manually to place a round in the chamber and put the weapon into battery.

Most, but not all, semi-automatic rifles have the charging handle on the right side. Some have the handle on the left side and accessible on the fore grip of the stock. The semi-automatic AR-15 rifle has the charging handle located above the bolt. Incidentally, the ‘AR’ of the Ar-15 stands for ‘ArmaLite Rifle,’ not ‘Assault Rifle.’ ArmaLite, the manufacturer who developed the rifle, was unable to meet military production requirements and sold the rights to Colt, the company established by Samuel Colt to produce his revolver in the mid-nineteenth century. The AR-15 is not the only semi-automatic rifle that resembles a military counterpart. The AK-47 can also be purchased from different manufacturers in a form that is incapable of fully automatic fire.

Advantages of Semi-Automatic Rifles

Additional shots with a semi-automatic rifle can be made very quickly, as fast as one can pull the trigger. This is almost as fast as that of a fully automatic weapon, but not quite. One doesn’t need to move the rifle from their shoulder to cycle the action, thus making it easier to regain the sight picture. Felt recoil is diminished by the cycling of the action and, in the case of the AR-15, by a buffer spring located in the butt stock. After-market additions are readily available, ranging from telescopic sights to a full stock replacement.

Disadvantages of Semi-Automatic Rifles

Because the semi-automatic rifles require only a squeeze on the trigger to shoot, ammunition supplies can be depleted in short order. Rapid fire results in a heated barrel that can burn the skin. Shooting a semi-automatic rifle, especially those utilizing gas operation, will cause soot and carbon buildups in the rifle, necessitating a thorough cleaning. Too much residue buildup can prevent the weapon from operating. Gas operated rifles are complicated and may need adjustments to control the amount of gas used in operating the action. Mechanical problems are more common in semi-automatic rifles and range from loading and extraction failures to blocked gas tubes. After-market accessories can change the type of firearm. For example, a popular, low-powered sporting rifle, the Ruger 10/22 can be altered to meet the legal definition of assault rifle or assault weapon by simply changing the stock. The Ruger would be functionally unchanged, but the cosmetic difference of the stock could require the owner to meet other legal requirements and face possibly substantial penalties upon failure to comply.

Writing failures with rifles

Here are a few of the most common opportunities to lose the reader’s willing suspension of disbelief.

  • Using the wrong weapon for the time period. Although a relatively minor number of lever-action rifles were used during the United States Civil War, each side relied upon weapons that were incapable of shooting metallic cartridges. Single-shot rifles shooting brass cartridges became popular for military use starting around 1870 and magazine-fed bolt-action rifles weren’t universally used until the mid-1890’s. Because of the robust design of bolt-action repeating rifles, their use continued through World War II and after. Semi-automatic rifles were developed prior to and during the First World War, but were usually found to be too complicated and fragile for use in the trenches. When one thinks of WWII, a conflict filled with fully automatic weapons jumps to mind, but six of the seven major countries that participated used the bolt-action rifle as their standard infantry arm. Only the United States issued a semi-automatic battle rifle, the M1 Garand, as the infantry soldier’s standard weapon and supplies of it were so limited in the early stages of the war that GI’s were forced to use the same bolt-action rifle that was used during World War I. Although the StG-44 was developed during WWII where it saw its first action, the Automat Kalashnikov, usually known as the AK-47, wasn’t developed until 1947; two years after World War II had ended and was, arguably, the first military rifle of the modern era.
  • In single-shot rifles, the weapon must be manually reloaded after each shot.
  • The trigger must be squeezed for each shot, particularly with semi-automatic rifles.
  • In rifles utilizing tubular magazines, only round-nosed ammunition can be used. The recoil from a high-powered cartridge could result in unintentional firing of cartridges with sharp-nosed bullets because the bullet nose will be resting on the primer of the next cartridge.
  • Both fixed and removable magazines must be manually reloaded.
  • Telescopic sight lenses are almost always covered when not in use. These covers must be removed before using the scope.
  • Not all high-powered rifles look like an assault rifle. Remington and Browning both make semi-automatic sporting rifles with stocks of well-finished wood. The magazines are removable and have a capacity of four rounds. The Browning has a pivoting plate that holds the magazine in place whereas the Remington slides into the underside of the receiver.
  • Dirty weapons malfunction. Since semi-automatic rifles, especially gas operated ones, are so complicated, each rifle should be field-stripped and cleaned following use.


Springfield Modelo 1873 | From the blog of Nicholas C. Rossis, author of science fiction, the Pearseus epic fantasy series and children's book

Springfield Modelo 1873. Source: WikiWand

A uniquely American version of the single-shot rifle is the hinged action found on the Springfield Trapdoor rifles and carbines (a shorter rifle) of the U.S. Army, following the Civil War. To operate, a catch near the hammer is released and the bolt pivots upward, ejecting the spent brass. A new cartridge is inserted and the bolt is pulled shut, which engages the locking lever. The external hammer is manually cocked before the trigger is pulled to fire the piece. George Armstrong Custer’s men of the 7th Cavalry were equipped with the Trapdoor Springfield and they discovered a fatal deficiency: The barrel heated with rapid fire, causing the chamber to contract and hold the cartridge in a tight grip. As if that weren’t enough, the extractor tore through the relatively soft cartridge brass and resulted in extraction failures. In the heat of close combat, the carbine with the spent cartridge stuck in the chamber became little more than a club.

Yet another type of single-shot rifle is the Remington Rolling Block, which operates just as the name implies. After firing, the hammer is cocked and a handle attached to the breech block is pulled back and down, causing the block to pivot downward and eject the spent cartridge. A new cartridge is inserted and the bolt handle is pushed forward to place the weapon into battery. These rifles were known for their accuracy, particularly at longer ranges.

The Spencer Rifle/Carbine was a lever-action rifle developed during the American Civil War and featured a unique approach to this type of action. This rifle featured a seven-round, tubular magazine that ran through the butt stock and an action that did not automatically cock the hammer while cycling. To operate, the shooter must first bring the hammer to half cock then pull the trigger guard downward. This ejected the spent cartridge. However, ‘ejected the spent cartridge’ may be too generous a term. Although pulling the trigger guard down did remove the spent cartridge from the chamber, it didn’t fling the brass away. Instead, it simply lay in place inside the receiver. The shooter would have to invert the rifle to discard the brass or pull it out with his fingers. Pulling the trigger guard back up chambered a new round. The shooter then had to pull the hammer to full cock by hand in order to shoot the round. Reportedly Abraham Lincoln’s favorite weapon, Confederates referred to it as “That damn’ Yankee rifle you load on Sunday and shoot all week.”

I hope this helps with your writing. The next installment will cover shotguns.