Cannon were identified by the weight of ball they were capable of throwing. By the 1600’s this became standardized. Their calibers went from the smallest – a two pounder used with swivel guns, mortars and small bore cannon on specially made carriages, to the largest – a fifty pound garrison gun.
The distance or range varied tremendously by the size of the ball and the amount of powder used to propel it. This proved to be very dangerous work for gun crews as cannon did explode, showering the crew with deadly metal shards. Factors that could come into play in which this occurred: in the heat of battle, artillerists expert in the balance of powder and shot per gun could inadvertently add too much powder; mistakenly insert two canisters (measured powder packed in paper); add a bit more powder to send a shot further to hasten the enemy’s retreat; improperly swab the barrel; improperly wade hot shot; or fail to remove unspent powder. In addition, shells sometimes exploded prematurely, or the weapon failed due to fatigue of iron or poor manufacture of the barrel.
Projectiles can be grouped into the following: cannon ball or shot, shell, canister or case shot, grape and pineapple, split shot, chain shot, bar shot, and hot shot. Each will be explained further in that order.
Cannon ball or shot was a sphere cast in iron. Mass times velocity gave it its most destructive punch; therefore it was less effective at a greater range. Fired in a flat trajectory, the iron ball was meant to bounce upon impact, like a stone skipping over water until it slammed into a line of infantry with the intent to behead or disembowel one or more soldiers packed tightly in ranks. Joseph Martin writes of soldiers eagerly chasing after spent British cannon balls that rolled harmlessly among them. Lugging the ball to the artillery officer, the ball was immediately added to the American munitions to return the favor; meanwhile the soldier was rewarded with a ration of rum for each ball he retrieved.
Shells were cast iron balls, but during pouring, were molded to have a hollow core. A small tube was figured into the manufacture so powder could be poured inside; this also enabled a fuse to be added. There were two basic types, non-fuse and fuse. The former, when fired, was expected to generate enough friction heat against the inside of the shell that it would ignite either while in route or upon impact. The second had a fuse inserted that was ignited prior to the shell being fired. If timed right, the shell would be over enemy troops when it exploded, raining down deadly steel shards. Unfortunately, as already noted, the shell sometimes exploded while leaving the barrel, which had a disastrous effect on the gun crew.
Canister or case shot and grape evolved from what were known as scatter projectiles. The earliest muskets would use ‘buck and ball’ when the commander wanted a more effective punch with his line of infantry. Beside a cartridge of ball, additional smaller pieces of lead were added creating a fanning effect when the gun was discharged. In the fourteen hundreds, stones and bits of metal were encased in a wad of cloth or leather giving the cannon more of a fowling piece or shotgun effect.
Canister was a thin metal cylinder filled with iron balls. Case was the same thin cylinder filled with lead musket balls. The cylinder was fixed to a ‘sabot’, French for wooden shoe. A strong seal is required to trap propellant gasses released from the powder’s explosion and keep projectiles centered in the barrel. This necessary gap is referred to as the windage. Wadding filled the role for solid shot and shell. The wooden ‘shoe’ or sabot did the same for canister and case. When released, the thin outer cylinder was immediately shredded by the shock of the explosion and its shared metal, along with the iron or lead balls, created a deadly cone pattern: in effect a volley from infantry with a two to three hundred yard range.
Grape shot was used when a longer range was needed. Similar to canister and case in its destructive affect on infantry, a canvas or leather bag contained the lead or iron balls which were half in size as musket balls instead of the thin metal covering. To make such an unwieldy container easier for gun crews to carry and load, a center rod ran up from a wooden base enclosed by the bag. The bullets were stacked around the rod and a length of cord was continually lashed around pulling the bundle into a shape that was both manageable and could fit the caliber of gun from which it would be shot. It was similar to a bunch of grapes thereby received its name. Pineapple shot was a variation of grape shot. When grape and case were used together, the result produced a killing field of up to 600 yards.
Split shot, per its name, was simply a solid ball halved then bound together. Loaded as one shot, upon firing, it separated with each half taking a different and unpredictable path due to asymmetry.
Chain shot was generally used aboard ship as it was designed effectively to carry away masts and rigging. Either split shot (two halves) or two solid shot were connected by a length of chain. Upon firing, each shot would pull in a different direction creating a rotating motion around a center mass. On land, it was most effective against a cavalry charge, taking out the horses legs or gouging a chunk of infantry in line.
Bar shot was similar to chain shot except a metal bar attached the shot at each end. The bar was one to two feet long. A type of this was referred to as a sliding shot. The connecting bar was actually two bars which, upon firing, would slide over each other by connecting grommets that expanded the distance between shot as well as its destructive force. All forms of bar shot were called angel shot for its appearance in flight to deliver a not so angelic impact.
Hot shot proved to haunt a gun crews’ sleep. Iron shot was heated in a portable forge that was brought to the rampart or upon the field of battle until red hot. A charge of powder was loaded but with a tight fitting dried wooden wad that was tightly rammed on top.
Wet cloth and oakum soaked in water were rammed home, acting as insulation between the hot iron and susceptible powder. The heated shot was then rapidly brought to the gun and loaded and fired as quickly as possible. This type of shot was most effective in ship to ship warfare and against fortifications housing supplies or munitions in wooden structures.
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