Allen Guelzo wrote a book about the battle of Gettysburg “Gettysburg: The Last Invasion” , in which he says some confused things about smoothbores and rifles. One of my regular readers noticed and mentioned this some time ago.
“Rifling bestowed greater range and accuracy on a musket, but it did so at the price of forming a trajectory for the bullet which “dropped” rather than went straight to a target. To hit a target thus required exact knowledge of the speed and distance of a target, something which in battle was rarely available.”
Which has left Wiki thinking that rifle bullets had curvy paths while musket balls flew straight. Not so!
Here’s a decent discussion ( by RogueOne). The key point is that a spin-stabilized bullet can be pointy yet not tumble: so it has a smaller cross-section and experiences less wind resistance. So it goes farther.
All the time that the bullet is flying, it’s dropping, under gravity. If it goes twice as far as a musket ball, that takes twice as long – and it drops four times as far. D = 1/2 g t^2 – one of the secrets of the Occident, known to but a few.
Guelzo suggests that people couldn’t really take advantage of the rifle’s greater range: but they could. The Springfield was sighted for 100, 300, and 500 yards – and when 15,0o0 Rebels are coming at you, you have a decent chance of hitting somebody at the greater distances possible with a rifle. Well-trained sharpshooters could even be decently accurate at those ranges, as Sedgwick found.
Charges didn’t work as well as they had with muskets.
Modern rifles have considerably higher muzzle velocities. Assume that one has four times the muzzle velocity of an 1861 Springfield: then it will take 1/4 the time to reach the same target, and will drop 1/16th as far. A flatter trajectory. How do we do it? Velocity !