Ammunition
The simplicity of the musket design allowed it to fire a variety of ammunition. The simplest ammunition for musket was the round ball, which was literally just a round ball of lead. Round balls were intentionally loose fitting in the barrel so that they could quickly be loaded even after the barrel had been fouled by numerous previous shots. This loose fit, combined with the poor aerodynamics of the round ball led to the musket's inaccuracy beyond 50 to 75 yd (46 to 69 m) or so. Muskets could also fire smaller lead pellets called lead shot or buckshot, which struck a wider area but with less force than a single lead ball. Round balls could be combined with buckshot to produce buck and ball ammunition, which combined the wider area of attack of shot with the large mass of the round ball.
Musket balls were of a diameter considerably larger than today's modern rifles—the Brown Bess fielded a caliber of more than .75". With its soft, all-lead composition, the ball would easily flatten or burst on contact, much like a modern soft-point bullet. Together with its large size, this meant it could cause large wounds. The smooth bore muskets of the Brown Bess period had considerable hitting power and were able to penetrate the armor of the day, but had limited accuracy due to the lack of rifling in the barrel.
The minié ball, which despite its name was actually bullet shaped and not ball shaped, was developed in the 1840s. The minié ball had an expanding skirt which was intended to be used with rifled barrels, leading to what was called the rifled musket, which came into widespread use in the mid-19th century. The minié ball was small enough in diameter that it could be loaded as quickly as a round ball, even with a barrel that had been fouled with black powder residue after firing many shots, and the expanding skirt of the minié ball meant that it would still form a tight fit with the barrel and impart a good spin into the round when fired. This gave the rifled musket an effective range of several hundred yards, which was a significant improvement over the smooth bore musket. For example, combat ranges of 300 yards were achievable using the rifled muskets of the American Civil War. While rifled muskets can fire other ammunition like round ball or buck and ball without issues, they were generally only issued minié ball ammunition. A rifled musket can also technically fire lead shot, but it does not pattern well due to the rifled bore. A smooth bore musket could also technically fire a minié ball, but without the spin imparted by a rifled barrel the minié ball would tumble and would not be accurate.
Musketeers often used paper cartridges which have very little in common with modern rifle cartridges. A musket cartridge consisted of a pre-measured amount of black powder and ammunition such as a round ball, Nessler ball or Minié ball all wrapped up in paper. Cartridges would then be placed in a cartridge box, which would typically be worn on the musketeer's belt during a battle. Unlike a modern cartridge, this paper cartridge was not simply loaded into the weapon and fired. Instead, the musketeer would tear open the paper (often with his teeth), pour the powder into the barrel, follow it with the ammunition (and possibly the paper as wadding if not using a minié ball), then use the ramrod as normal to push it all into the barrel. While not as fast as loading a modern cartridge, this method did significantly speed up the loading process since the pre-measured charges meant that the musketeer did not have to carefully measure out the black powder with every shot.
The superior accuracy and effective range of the Minié ball and rifled musket led to its rapid and widespread acceptance, while the simple musket ball and smooth bore musket gradually fell out of favor. The later development of the bullet cartridge accelerated the demise of the older technology. Despite this, musket balls continued to be used until well into the late 19th century, as regular armies and militias had accumulated vast stores of them over time.
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