The Brown Bess was the most popular musket of all time, it saw service as your everyday British laymans gun from early 1700's to mid 1800's. These smoothbore muskets were very, extremely, inaccurate. Have you ever wondered why the British armies stood toe to toe with their enemies and shot each other down like cows? This musket is the reason why! The Brown Bess, just like most other smoothbore guns, was designed long before rifling was discovered. Rifling is a fundamental part of accuracy that if done without will leave you with a group of 1 foot at 15 feet!
The Brown Bess musket was a flintlock musket. The flintlock musket was a much smarter design than the previous models such as the matchlock musket, and far easier to make than the wheel lock musket. The flintlock carried a piece of flint (a kind of stone) in the place of a where a hammer would be on a more modern rifle. When you pulled the trigger the flint would descend, striking a piece of steel on the way down and sparking the powder in the priming pan, which discharged the gun.
Even after rifles were invented (called rifles because of the rifling found in the barrel) some generals proffered the faster loading smothbore Brown Bess muskets. The newer muzzle loading rifles, like the Kentucky Long Rifle, took a much longer time to load because the shot had the fit in the barrel much tighter for the rifling to be effective, and underneath the ball would be the patch. So altogether it was a very tight squeeze to get that ball down the barrel. But the effect was well worth it. Kentucky Long Rifles were able to hit targets at 350 yards! And certain records show even better shots! Kentucky Rifles were made in both flintlock design and later, cap and ball.
So the British were not exactly "nuts" during Revolutionary War time period, they just lacked technology. And by the way many of the Americans at that time had smoothbore muskets too. But it is true that the British held to their mode of volleys longer than any other country.
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