Ordnance Depot

Ordnance Depot

The Ordnance Depot is a reference database for identifying, understanding, and interpreting ordnance that you might find underwater. The Depot is curated by Bill Utley, a specialist in ordnance and archaeology.


  • Anti-tank mine.
  • German World War II bomb.


Everyone knows that, among thousands of other facts, the bad guys are notoriously poor shots; that you have to circle the wagons to protect against Indian attack; that feuds were settled in the old West by two men and the fast draw; that Vikings wore horned helmets; that Strategic Bombing shortened WWII, and that Columbus discovered the Americas. These are all part of our historical knowledge – and they are all wrong. Like most things in the past few hundred years, common usage, myth, “Hollywood,” and poor scholarship all combine to recreate history. Regrettably, the same thing applies to Ordnance.

It would surprise most people to learn that no one has been killed or injured in battle by shrapnel since the middle of WWII. It would also surprise most people to learn that unlike what is pictured in the movies and television, you can’t outrun a blast pressure wave from an explosion. Most people wrongly think that if a grenade, shell or bomb fails to explode, it is basically harmless. And most think that the older a piece of ordnance, the more likelihood that it is no longer viable - a wrong and deadly assumption. Hundreds of people worldwide are killed or injured every year from “old” ordnance through ignorance, stupidity, carelessness, and misinformation. And historians, archaeologists, scriptwriters, and reporters continue to use all the wrong terminology when writing about ordnance.

The purpose of this first section of The Ordnance Depot is to start everyone speaking and writing the same, correct language. This of course is historically important – after all we don’t call “points” “arrowheads,” “sherds” “pottery chips," or “treenails” “wooden spikes.” But it is also important when speaking with ordnance professionals – something most archaeologists will have to do at some time in the field - to be able to accurately describe the items in question, and to understand their potential.

What follows then is a “dictionary” if you will, of ordnance and ordnance-related terms. It is not meant to be all-inclusive – that would take volumes. But it will include most of the common terms archaeologists can be expected to encounter, and later additions will be made. Future sections will address specifics of guns, ammunition, and ordnance-related equipment.


Black Powder: The modern formulation for black powder (post 1850s) is: 75% potassium nitrate (salt-peter) , 15% charcoal, 10% sulphur, although formulation percentages and ingredients can vary slightly with the manufacturer. Black powder is both a low explosive and a propellant.  Black powder does not degrade with age if it is kept in a sealed, dry environment – such as the inside of a shell (see “Shell” below). Black powder is hydroscopic – it readily absorbs moisture. When wet, it is benign.  When dry, it can be set off by heat, shock, or friction. The origin of the phrase “fog of war” comes directly from the smoke created by black powder. When tens of thousands of men fired muskets and cannon, the effect was to completely blanket the battlefield in a heavy  “fog” of smoke, obscuring everything. Prior to the 19th century, black powder ingredients and percentage mixtures could vary wildly. Archaeologically, it would always be a good idea to investigate the makeup of any recovered black powders.

It is commonly stated as fact that the Chinese invented black powder. However, there is no direct evidence of this. The Chinese certainly invented some types of pyrotechnic powders, but there is nothing to indicate that any of these were black powder. Some historians try to make a case for Francis Bacon as the inventor, or an unknown Arab source. Absent any conclusive evidence, it would be historically inaccurate to pinpoint a specific source.

When unconfined, black powder does not explode but burns rapidly, producing gasses. It is these gases, when confined, that cause the container to rupture in an explosion.


Bolt: When barrel rifling was introduced, solid, round ammunition was no longer practical. Ordnance now took on a more aerodynamic bullet shape. The word “bolt” replaced the term “shot” for solid ammunition for rifled guns.

30lb Hotchkiss Round

30 pound Hotchkiss bolt – 1860s - Old Fort Niagara collection. This is an extremely rare piece, previously found in only one other location – the West Point Firing Range. Note the lead sabot. Photo by Bill Utley.

Bomb: Old military terminology. The word “bomb” originally referred to a “mortar bomb”, the round explosive shell fired from a mortar.


Bomb: Modern military terminology. By the beginning of the Great War (WWI), the term bomb meant the new aerial bombs, hand thrown, grenade-type or improvised explosive devices used in trench warfare. After WWI, “bomb” in military terms came to mean aerial bombs.


Bomb: Civilian usage. The word “bomb” has taken on a generic civilian meaning, largely referring to any explosive device that is improvised as opposed to manufactured in a factory. Bomb technicians and military explosive ordnance disposal experts refer to this type of “bomb” as an Improvised Explosive Device (IED). While news organizations seem to have discovered the term IED in the past few years, the term has been in use in the professional community for over 40 years.


Bomb: Modern military usage. The term generally refers to aerial-dropped ordnance, guided or unguided.


Brass Monkey: A square brass raised platform used to stack ammunition in a pyramid form. “It was cold enough to freeze the balls off a brass monkey” is only dirty in the mind of the uninitiated. It means that it was cold enough to shrink the brass causing the rounds to tumble off.


Broad Arrow: While not a piece of ordnance, it is included here because it is generally mistaken as a British ordnance mark. It is, in fact, a British government ownership mark, not exclusive to ordnance. The misunderstanding originates because it usually appears on most British 18th and 19th century cannon. The author has seen the mark on rain spouts in a fort in Jersey for example (UK, not US!). Even on cannon however, it does not necessarily denote the origin of the piece – captured pieces were incised with the mark.

Broad arrow incised on a gun at Brimstone Hill Fortress, St. Kitts. The arrow has been chiseled in at a later date – note the thin, shallow, irregular lines.

Broad arrow incised on a gun at Brimstone Hill Fortress, St. Kitts. The arrow has been chiseled in at a later date – note the thin, shallow, irregular lines.

Shot from Old Fort Niagara Marked with Broad Arrow

Shot from Old Fort Niagara, Youngstown, NY. This would have been used by the British sometime between 1759 and 1815. It is not usually possible get a national origin or to date shot absent other information about the site and gun usage at the site. This is unusual piece since it is marked with a broad arrow, not a normal practice for artillery rounds.

Canister: Also called “Tin Case Shot”, canister was an anti-personnel round used in the 18th and 19th centuries. It was essentially a large shotgun shell consisting of a tin-galvanized iron cylinder brass-tacked to a wooden base, and filled with either iron or lead balls. Because of the thin case container, intact canister rounds are extremely rare. Canister contains no internal explosive and was designed to break apart at the muzzle from the force of the firing, spreading out the contents. Canister was used against personnel in the open, at ranges under 400 yards.

American Civil War canister round with wooden base loading plug

American Civil War canister round with wooden base loading plug.

Cannon: This is the generic term for any large, smooth bore, muzzle-loading gun, used before the introduction of breach-loading rifled guns. Guns and types will be discussed more specifically in a later article. See also Gun.


Cannonball: The colloquial term used by laymen to describe all types of round, smooth ordnance. While not specifically incorrect as a generic term, it is not type specific, and should not really be used by archaeologists or historians except in the most general of situations.


Carronade: First manufactured by the Carron Ironworks Company in Scotland, the carronade made its first appearance in the Royal Navy in 1779, and was soon copied in many countries. It was a short barreled, short range weapon that was able to use less powder to fire larger shot with more striking power. Its relative small size reduced the weight making it easier to handle and making it possible to put more on board a ship. Early carronades had a central pivot on the bottom of the gun rather than side trunnions. The central pivot meant that they had to be mounted on a sliding carriage rather than traditional wheeled gun carriages. Later carronades had trunnions and are often called “gunnades”, which appears to be more modern than contemporary terminology. Carronades fired shot, grape, and canister, and calibers for carronades ranged from 6 to 68 lbs. Like guns, carronades were categorized by the weight of their shot. Carronades were shipboard weapons, but they can be found in fortifications. They were not used in land warfare outside fortifications.


Carronades with trunnions on garrison carriages – overlooking cul-de-sac, Brimstone Hill Fortress, St Kitts.

Case Shot: see Shrapnel Shell.


Cordite: A British-developed derivative of smokeless powder experimentation, cordite is a gelatinized mixture of nitrocellulose (guncotton), nitroglycerine, and vaseline that produces a paste when dissolved in acetone. The paste was squeezed through dies, forming a solid, stringy material. The formulation varied over decades. Cordite was a very common propellant, especially in WWI. Cordite burns but will not explode if unconfined. Also, from the author’s own experience, it will not degrade even in decades-long exposure to salt water.


DUD: Term used by the public to denote unexploded ammunition that has taken on the wrongful connotation meaning “Safe.” It is not a term generally used by ordnance professionals. It can also be used for anyone who disregards explosive safety.


EOD: Explosive Ordnance Disposal. The personnel in EOD are military, and their primary function outside of a war zone is to deal with the handling, identification, and disposal of military ordnance, regardless of the age of the ordnance. In the United States, Canada, France, Belgium, Hungary, Japan, and Britain, EOD personnel handle all found military ordnance. Other countries may have military or civilian bomb technicians, or a combination of both, handle military ordnance. In Germany and South Africa for example, most historic ammunition is rendered safe by civilian bomb technicians.


Fragments: The pieces of outer casing of a shell or shrapnel round, the casing and interior parts of a hand grenade, or the casing of any other type of military round that explodes.

Shell fragment from rifled shell showing threading for fuze.

Shell fragment from rifled shell showing threading for fuze.

Shell fragment from smooth bore artillery.

Shell fragment from smooth bore artillery.

Friction Primer: First making its appearance in the 1840s, the friction primer was to artillery what the percussion cap was to small arms. Consisting of a long tube filled with black powder and capped with wax at the open end, the top “T” contained a friction sensitive mixture, and a twisted wire with a loop, serrated at one end. The tube was inserted into the vent hole, piercing the powder bag. The gunner then attached his lanyard to the small loop, and when pulled, the friction end of the wire sparked the friction sensitive compound, igniting the black powder in the tube and sending a flame into the main powder charge. The resultant discharge kicked out the used tube. It would be common around mid to late 19th century artillery positions to find the small wire loop which separated when the lanyard was pulled.

Intact Friction Primer – recovered from looter  - USS Tulip - from the US Navy History and Heritage Command Collection.

Intact Friction Primer – recovered from looter - USS Tulip - from the US Navy History and Heritage Command Collection.

Fuze: Prior the 20th Century. CAUTION! All percussion and concussion fuzes can still fire upon impact if dropped! 18th and 19th century fuzes are usually either brass or wood.

Timed fuze: Incorporates a finely-milled black powder train that the gunner can “cut” to set a precise time to explode. The fuze is ignited by the flash of the gun firing.

Percussion fuze: For rifled ordnance – designed to explode when the nose of the round strikes a static object. These fuzes incorporated a percussion cap (the same as used on rifles and  pistols) that fired into a power train upon impact and detonated the main charge.

Concussion: For spherical shells – designed to explode when striking a hard object. It does not have to land on the fuze. Concussion fuzes incorporate a chemical liquid compound such as sulphuric acid in a glass tube that is designed to ignite a second compound upon contact, or a glass vial with liquid fulminate that will explode when impacted by lead balls incorporated into the fuze. CONCUSSION FUZES ARE PARTICULARLY DANGEROUS IF ENCOUNTERED UNFIRED OR MISFIRED!

Combination: Two independent functions in the same fuze– timed and percussion – whichever initiated first after firing.

American Civil War era wooden mortar time fuze. Note the striations – the fuze could be cut on those lines.

American Civil War era wooden mortar time fuze. Note the striations – the fuze could be cut on those lines.

Fuze: 20th and 21st Centuries. As artillery became more sophisticated, so too did the ammunition and fuzes. While black powder-train fuzes were still used through WWI, impact-type fuzes became more common. World War II and later saw the revolutionary new proximity, radar, very sophisticated timed and anti-handling fuzes, and super-quick fuzes, among many other innovations. Fuzing types in the 21st century are prolific and especially deadly.


Grape: Also called grapeshot, like canister, it was an anti-personnel round. Composed of iron balls (some early grape had lead balls) that were stacked generally in three tiers, with wooden spacers and an iron rod through the center to join the tiers, the whole wrapped in heavy cloth. Grapeshot generally contained larger balls than canister (9 balls vs 27 balls for a 12-pdr Napoleon, for example). While still in use on land in the 1860s, it was becoming obsolete. Naval grapeshot was called “quilted grape” due to its resemblance to a quilted sack of grapes. There is no distinct dividing line between the size of canister balls and grape balls. While something like a one-inch ball might intuitively look like grape, it could be canister for larger ordnance.

Quilted Grape round - American Civil War

Quilted Grape round - American Civil War

Gun (Smoothbore): Designed to fire on a flat trajectory, guns of the 17th, 18th, and 19th century were smoothbore weapons. They fired shot, grape, and canister, but because of their higher powder charge they did not fire shell, which had relatively thin walls that might burst in the tube upon firing. The gun was the primary form of artillery on land and sea for three centuries. The gun is, by far, the most common type of artillery encountered on board a warship, in a shore fortification, or on the battlefield. Guns are usually referred to by the weight of shot – for example 12, 18, 14, or 32-pounders. In spite of the advancement in accuracy and range imparted by rifling, smooth bore artillery was used into the latter part of the 19th century. In the American Civil War, half of the artillery used on both sides was smoothbore bronze “Napoleons,” favored because of their  proven reliability.


Gun (Rifled): The rifling of ordnance – adding lands and groves to the barrel – changed the shape of the battlefield. It allowed for the accurate firing of ordnance over longer ranges, and necessitated the reshaping of ordnance from round to pointed cylindrical. Rifling imparted spin to the round, making it more aerodynamic, thus adding accuracy and range. It also allowed the use of shells in all varieties of artillery. Early shells for rifled ordnance often had unreliable fuzing, and also smaller explosive chambers than their round counterparts for smooth bore guns. In US Civil War battles, for example, gunners often removed the fuzes and fired the rounds as bolts, meaning that they could easily be encountered in an archaeological setting since they did not explode.


Gunpowder: See Black Powder. This was the common term for black powder for almost 500 years – there was no other explosive or propellant used militarily, hence no need to differentiate.


High Explosive: These are explosives that detonate at speeds greater than the speed of sound – from 3 to 9 kilometers per second. While all explosives burn in the strictest sense, the speed of the burn for high explosives is faster than human senses can detect. High explosives require a shock wave propagating through the explosive at a rate greater than the speed of sound to cause detonation. While there are some shock-sensitive high explosives, all require the use of a blasting cap or a booster explosive to initiate. Unlike low explosives, high explosives will detonate if unconfined, and cannot be set off by a flame or spark source. All modern military explosives and fillers for shell, mines, bombs and grenades are high explosives.


Howitzer: Pre-20th century. A howitzer was a medium length, smooth bore artillery piece that used a small charge to fire rounds at a lower velocity and higher trajectory than a gun, but a lower trajectory than a mortar. It was designed to fire at troops sheltered behind fortifications or terrain. It had a shorter range than the gun, and used less powder. The shell was the initial primary round of the howitzer, but the later development of the shrapnel shell (case shot) which could be primed for an air burst, made it a preferred howitzer round. In an emergency, howitzers could also fire canister. It did not fire grape since howitzers were usually made of brass, and the iron balls in grape would destroy the inside of the barrel. Howitzers did not fire shot. They were almost exclusively land weapons, although because of their lesser weight, small land howitzers were often carried by larger 18th and 19th century warships for use in small boat actions. They are generally named by the diameter of their bore – for example 8 or 10-inch, but occasionally named for the weight of the shot they could, but didn’t fire (confusing, I know – ask your ancestors!). Howitzers usually are flat at the muzzle, without the swell of gun muzzles.


Inert: In terms of ammunition, it means that the ammunition is no longer capable of functioning as designed, and contains no viable explosive filler or live fuze.


Low Explosive: These are explosives that “deflagrate” – i.e. burn – at less than the speed of sound. Any explosive that propagates at less than 400 meters per second is considered a low explosive. They do not detonate. Unconfined, low explosives burn. Confined, the rapid accumulation of gases from burning causes a very rapid expansion of gas overcoming the container and causing it to burst. Low explosives are initiated by a flame or spark source. Black powder, smokeless powder, and pyrotechnic powders are examples of low explosives.


Mine: Originally called “torpedoes”, mines were and are  designed as anti-personnel, anti-ship, area-denial, and later anti-tank weapons. Made to sit underwater or buried on land, mines can contain from several hundred pounds (sea mines) to a few pounds (land mines) of explosive. Up to World War II, mines usually had a metal outer shell. During WWII mines were also manufactured from glass and wood (designed to defeat mine detectors).  Land mines generally have some type of impact, trip-wire, or rod-tilt fuzing. Post WWII land mines generally have some type of plastic or ceramic body.

Early sea mines generally had galvanic or impact fuzing, but as mines progressed in the 20th century, the fuzing also included increasingly sophisticated magnetic and acoustic fuzing systems. In WWII, the Germans used air-dropped sea mines as a land-weapon with a timed fuze. Fuzing on modern sea mines is so sensitive that naval EOD personnel have to have the metal filings removed from their teeth.

In the past several decades, modern armies have increasingly turned to air-delivered anti-personnel and anti-tank mines with EXTREMLY sensitive fuzing. All modern mines are EXTREMELY DANGEROUS. By one estimate, between 1945 and 1995, over 500 ships were sunk by leftover WWI and WWII mines. There are hundreds of thousands of WWI and WWII sea mines unaccounted for world-wide - a cautionary tale for underwater archaeology. There are still areas of Europe and North Africa that are no-go areas due to WWII mines, not to mention late 20th century battlefields around the world. There are millions of unrecovered mines left over worldwide from the wars of the 20th and 21st centuries.


Mortar: Pre-20th century. A mortar is a short-barreled weapon firing on a high trajectory. Mortars were commonly used against fortifications to lob shells over high walls and earthworks. They were only capable of firing shells or carcasses (a type of incendiary). Unlike guns and howitzers, mortar trunnions are rear-mounted. More of a land weapon, large mortars were cumbersome and in naval use were mounted in special “bomb” vessels for use in shore bombardment. They were made of both iron and bronze. Mortars were categorized by the diameter of their bore –10-inch for example. Americans should be familiar with mortars from the National Anthem – the “bombs bursting in air”, in this case, shells fired from mortars mounted on British warships.

10-inch British mortar from the Fort Niagara Collection.

10-inch British mortar from the Fort Niagara Collection.

Mortar: Modern. The mortar has survived modernized but essentially unchanged into the 20th and 21st century. While heavy mortars can be vehicle-mounted, most are man-portable and used as an infantry support weapon. It is the only weapon still in the modern military inventory that is still muzzle-loaded. It is also one of the few that is still smooth bore, using fins to stabilize flight. (The other smoothbore weapon is some tank guns, which fire fin-stabilized, discarding sabot (FSDS) ammunition.


Musket: A musket is a military, smooth bore, long gun. The terms “musket” and “rifle” are not   interchangeable.


Pederero: Also spelled “Petereros”, “Patterera”, and several other variations - there is no consensus spelling for “Pederero.” In any event, it was a gun ahead of its time, being a breach-loader. Because technology had not caught up with the science of artillery and metal working, Pederero were limited in caliber, and dangerous to the artillerymen as well as the enemy. The breach consisted of a removable block that could be pre-loaded, and inserted into the open breach. Thus one load could be in the gun while another was being loaded.  It would have been employed as a swivel gun.

17th century Pederero in the Old Fort Niagara Collection. This gun was excavated from the French fort at Crown Point, NY.

17th century Pederero in the Old Fort Niagara Collection. This gun was excavated from the French fort at Crown Point, NY.

Percussion Cap: The percussion cap was introduced for long guns and pistols the early 1820s effectively bringing firearms into the modern era, replacing the flint lock mechanism that had been in use for 200 years. The use of the percussion cap greatly increased the rate of fire, and was an all-weather firing system not encumbered by rain or high humidity. The primary ingredient for a percussion cap is fulminate of mercury. When the cap is struck by the gun hammer, it imparts a flame into the black powder in the chamber. By the 1850, percussion caps were beginning to be used in some artillery fuzing systems for percussion fuzes. Unfired 19th century artillery fuzing using percussion caps is still very much alive.

Archaeological Context Caution: Percussion caps are still used today by re-enactors and they can contaminate a site. It is difficult to tell a modern percussion cap from a historical one.

American Civil War era percussion cap tin with unused caps.

American Civil War era percussion cap tin with unused caps.

Fired percussion cap from the George Washington’s Ferry Farm Collection

Fired percussion cap from the George Washington’s Ferry Farm Collection

Rifling: Rifling, the lands (raised) and groves (indented) cut into the interior of a barrel, first came about in Germany in the 16th century. Rifling imparts spin to a projectile, increasing both range and accuracy, and were used as hunting rifles in Germany and Austria. The rifle also saw its appearance in 18th century America as the Kentucky/Pennsylvania hunting rifle. While it did see limited use in the American Revolution, as did the British Baker Rifle, its use is more mythology than fact. Until the 19th Century, few rifles could mount bayonets, making them useless for close quarter fighting, and were very slow to load. Used properly, units with rifles could be a battlefield equalizer. The British Light Division (The Rifles) was probably the premier unit in the Peninsular War in the early 19th century. However, a good unit armed with muskets could get three rounds off for every one rifle round, so it wasn’t until the middle of the 19th century that rifling for long guns and artillery gained popularity. It was only a natural extension once rifling of pistols and long guns became the norm in the second quarter of the 19th century, that artillery would also see a transition. This in turn required new ammunition forms for both hand weapons and artillery since it was impossible to get the hard iron of shot to conform to the rifling.

View of the rifling of a Union (American) 6.4-inch Parrott Rifle. This is an RML from the Old Fort Niagara Collection.

View of the rifling of a Union (American) 6.4-inch Parrott Rifle. This is an RML from the Old Fort Niagara Collection.

Two dropped .58 caliber Union Minie Balls, c1862-3 – for rifles. The base is hollow and expanded into the rifling when fired - From George Washington’s Ferry Farm Collection

Two dropped .58 caliber Union Minie Balls, c1862-3 – for rifles. The base is hollow and expanded into the rifling when fired - From George Washington’s Ferry Farm Collection.

Rifled Muzzle Loader (RML): During the transition period in the 1850s and 1860s, before the widespread acceptance of breach loading, old muzzle-loading smooth bore artillery saw some pieces re-bored for rifling. New pieces were cast and bored for rifling, but were still muzzle-loaders for the most part. Since they still had to be loaded from the muzzle, they came to be called Rifled Muzzle-Loaders (RML).


Sabot: Generally, a carrier attached to ammunition that is smaller than the barrel diameter. In the early days of rifling, a sabot prevented the escape of gases ahead of the missile thereby imparting both thrust and stabilizing spin. Upon firing, the sabot was forced into the barrel rifling, imparting spin to the round, thus stabilizing it and increasing range and accuracy. Sabots in the 19th century were made of lead or papier mache, or other materials softer than the barrel, to prevent firing damage and allow the material to form into the rifling lands and grooves. Sabots are still used today in some forms of smooth bore tank gun ammunition. Shell and case shot for smooth bore artillery also had an attached wooden sabot which ensured that the round had the fuze facing away from the powder charge. The sabot separated from the round as it left the barrel.

Rare papier mache sabot from an American Civil War Shenkle Shell – recovered from looters - from USS Tulip. Note the remains of the shell in the first photograph. From the US Naval History and Heritage Center Collection.

Rare papier mache sabot from an American Civil War Shenkle Shell – recovered from looters - from USS Tulip. Note the remains of the shell in the first photograph. From the US Naval History and Heritage Center Collection.

Rare papier mache sabot from an American Civil War Shenkle Shell – recovered from looters - from USS Tulip. Note the remains of the shell in the first photograph. From the US Naval History and Heritage Center Collection.

Rare papier mache sabot from an American Civil War Shenkle Shell – recovered from looters - from USS Tulip. From the US Naval History and Heritage Center Collection.

Shell: A hollow piece of ordnance loaded with black powder with a black powder timed-fuze system or later a combination fuze. When a shell explodes, the outer casing breaks into fragments, - NOT shrapnel - and these are the destructive mechanism. The term “explosive shell” is redundant. Shells were fired solely at higher angles in howitzers and mortars until the mid-19th century. In modern (post 1850s ordnance), shells are any form of cannon ammunition that is designed to explode. Black powder shells for both smooth bore and rifled artillery fragmented upon exploding into large pieces, so while deadly, were not particularly efficient. Modern shells are not filled with black powder but with a variety of more modern explosives that create small and sharper case fragments.

Cutaway of 18th century shell with powder bag (it was packaged as a complete round by the 18th century) Fort Frederick, MD

Cutaway of 18th century shell with powder bag (it was packaged as a complete round by the 18th century)
Fort Frederick, MD

Spherical Case Shot: See Shrapnel Shell.


Shot: The correct term for solid ammunition used in smooth bore ordnance. Shot is a solid, round projectile, commonly called a “cannonball” that imparts its destructive power through kinetic energy. Early shot was dressed stone or lead, but stone proved too brittle to withstand the shock of firing, and lead proved too soft. Early attempts also included a marriage of lead and iron. Both stone and lead were soon replaced by cast iron round shot. It does not explode but it can break on occasion if it hits solid resistance such as stone.


Shrapnel Shell: The shrapnel shell was invented in 1784 by Lieutenant Henry Shrapnel of the British Army, and originally called Spherical Case Shot. It saw its first general use in the Napoleonic Wars, where it was the secret weapon of its day. Before that time, explosive ordnance was limited to the shell. Shrapnel shells are essentially a conversion of shells with a different bursting charge and the addition of interior fragmentation in the form of round iron or lead balls, or in the latter half of the 19th century, lead ammunition from rifled firearms. The term “shrapnel” refers exclusively to these inclusions. The breakup of the outer casing of shrapnel rounds created “fragments.” Shrapnel rounds were in common use up through the early years of World War II, and the author has seen Japanese shrapnel rounds on a 1944 WWII Pacific battlefield.

To make matters confusing, the American’s never used the “Shrapnel Shell” terminology, and called their 19th century equivalent “Case Shot.”

American Civil War era case shot using Williams Cleaner bullets as shrapnel. Old Fort Niagara Collection

American Civil War era case shot using Williams Cleaner bullets as shrapnel. Old Fort Niagara Collection.

Smokeless Powder: A general name for several varieties of powder. The first smokeless powder was invented in 1846, a nitrocellulose mixture called “guncotton.” It was highly unstable so it was not until 1884 that stabilization made it a practical explosive. In 1888, Alfred Nobel gelatinized the mixture, making it a practical propellant – a mixture of 45% nitroglycerine, 45% guncotton, 10% camphor, calling it “Ballistite.” Thereafter, various governments tinkered with the formula, creating various smokeless powder mixtures. While not truly smokeless, these powders have considerably more power than black powder, were less susceptible to damp, and created considerably less battlefield smoke. First used in long guns and handguns, it eliminated the “fog of war” since it burned cleaner and more efficiently than black powder. It also extended ranges for all weapons.  There are various formulations for smokeless powder. See also Cordite.


Render Safe Procedure (RSP): The term used by bomb technicians for the process of making an explosive item safe.


Swivel Gun: A small caliber gun, usually around a one to three pound caliber range, mounted on a base that was itself usually attached to something like a ship’s rail. The gun was strictly a very close range anti-personnel weapon, firing a small shot, or odds and ends of metal. Swivel gun ammunition can easily be mistaken for individual pieces of grape.


Tin Case Shot: See Canister.


Torpedo: Old terminology. Before the advent of the submarine, the term torpedo meant what we call today a mine. This could be something underwater, or planted in the ground. Farragut’s alleged cry of “Damn the torpedoes, full speed ahead” at Mobile Bay in Alabama during the American Civil War meant that he was ignoring the presence of Confederate torpedoes (mines). Early mines were either fired galvanically with a battery on shore and a wire run to the mine, or by a percussion fuze.


Torpedo: Modern terminology. With the advent of submarine warfare, there was a need for a stand- off weapon to allow an attack from a distance. This in turn led to the development of the modern torpedo, fired underwater from submarines, from surface launchers on torpedo boats and destroyers, dropped from planes beginning in WWII, and even in some instances, from   shore batteries. Torpedo warheads contain hundreds of pounds of explosives.


Training or Training-Practice Rounds: This is ordnance whose main explosive chamber is empty, solid, or contains inert material. However, some training rounds can contain either a tracer material to observe flight, or a small bursting charge to observe impact. While the bursting charge is not designed to shatter the container, it can cause injury if mishandled. Caution should be exercised when a suspected training round is encountered until declared safe by an expert.


UXB: Unexploded Bomb - term used by bomb technicians to denote Unexploded Bombs (aerial).


UXO: Unexploded Ordnance - term used by bomb technicians to denote Unexploded Ordnance.


Windage: The gap between the sides of the round and the interior sides of the barrel. All muzzle-loading weapons – pistol, long gun, and artillery – smooth bore and rifled – required that the rounds being loaded were smaller than the interior diameter of the barrel. This was due to the fouling qualities of black powder, which does not completely burn away when ignited and deposits a residue on the inside of the barrel. This in turn gradually decreases the diameter of the barrel, making subsequent loadings more difficult. Even muzzle-loading nineteenth century rifled barrels required windage. The rifling was engaged on rifled artillery by means of a sabot of some type that expanded upon firing and engaged the rifling. The calibers of the weapons (the interior diameter of the bore) and the actual caliber of the round for the weapon will be different, the round itself being smaller. For example, the caliber for 18th century British muskets was .75, but the ball itself was around .69 to .72. Because of the windage gap, upon firing, rounds tended to bounce their way down the barrel, exiting in the direction of the last bounce. Shot at with a musket, it was an unlucky man indeed who was hit at over 70 yards. Accuracy with smooth-bore artillery, while not precise, was better than with a musket since the tolerances of the rounds were smaller, and the bore was generally cleaned out after ever shot.


William (Bill) Utley is a retired US Government bomb technician. He has a BA in history, a Masters in Criminal Justice, and a Masters in Military History. He has been an avocational archaeologist, both maritime and terrestrial since 1983.

Feedback, questions, concerns, recommendations, requests, and corrections are encouraged. Please contact editor at [email protected].

Translate »