Muskets were smoothbore, large caliber weapons using ball-shaped ammunition fired at relatively low velocity. Due to the high cost and great difficulty of precision manufacturing, and the need to load readily from the muzzle, the musket ball was a loose fit in the barrel. Consequently on firing the ball bounced off the sides of the barrel when fired and the final direction on leaving the muzzle was unpredictable.
Barrel rifling was invented in Augsburg, Germany at the end of the fifteenth century.[5] In 1520 August Kotter, an armourer of Nuremberg, Germany improved upon this work. Though true rifling dates from the mid-16th century, it did not become commonplace until the nineteenth century.
The concept of stabilizing the flight of a projectile by spinning it was known in the days of bows and arrows, but early firearms using black powder had difficulty with rifling because of the fouling left behind by the combustion of the powder. The most successful weapons using rifling with black powder were breech loaders such as the Queen Anne pistol.
Early muskets were handcrafted and rifling a peculiar difficult skill. Poorly made weapons were also typicaly poorly rifled and therefore inaccurate. The reason early battles were fought so closely in line order was that most weapons could not hit "the braod side of barn" at any distance. This changed as weapons manufacturing refined and killing at greater distances became possible. Hunting for food one didn't want to waste shot or powder either.
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To identify a ball
Pick up the musket ball with forceps and examine it for a mold seam. Because of the crudeness of some 18th-century molds, the seam of an authentic musket ball may be slightly offset.
Hold the musket ball in the forceps and look for a round, raised bump on the ball. The bump, known as the casting sprue, was made in the inlet channel of the mold.
Examine the ball for a white, lead-oxide patina. Musket balls buried underground for years develop a coating. However, the presence of pine and oak trees in the excavation area can darken the sheen of an authentic musket ball to a deep reddish-brown.
Measure the ball's diameter. 18th-century musket balls range in diameter from 0.39 inches to 0.69 inches. The British Brown Bess musket carried a 0.693 inch diameter ball. American rifles took smaller balls, measuring less than 0.60 inches in diameter but no smaller than 0.39 inches.
Weigh the ball if its shape is not spherical. A fired musket ball may have hit a tree or other object and changed shape. Calculate the ball's diameter with the formula: Diameter in inches = 0.223304 x (Weight in grams) to the power of 1/3. Compare the calculated diameter to the measurements before.