For most of the existence of the firearms, two glaring conditions where evident. For the longest time black powder, that is a smelly mixture of potassium nitrate (saltpeter), carbon and sulfur that stinks when fired (probably due to sulfur, a primary component of smelly odors) was employed. The common fact is that black powder guns fired primarily round projectiles, either rock or metal.
Musket Pistol & Rifle
Take the Brown-Bess musket of the British Empire. It had a .75 inch bore that pumped out .69 inch standardized lead balls. That’s 6/100th of an inch difference and was referred to as “windage”. Muskets are smoothbores like shotguns. The windage allowed reloading, even as the deposits of fowling continued to build shot to shot. Muskets where good on single targets out to about 50 yards, man or deer. As the tactics where referred to as “Napoleonic” massed groups of men fire into the other sides ranks and then closing for the bayonet charge. Because of the close quarter ranks, the musket was effective out two about a 100-yards.
Problems of Black Powder
Black powder has some problems as a propellant. As only 45% of a black powder charge is converted to gases that expand and due the work of pushing the projectile from the muzzle, black powder is not very efficient. Everything else are solids in the form of smoke or fouling in the barrel. Being hydroscopic, these deposits attract moisture and is the chief source of corrosion in muzzle loader/black powder firearms. By weight typically nearly a third is left in the barrel as fouling. Some black powder mixtures burn cleaner than others. Smokeless powders (misnomer as there is a little smoke) has about 3 times the gas producing and therefore energy of the black powders. Some modern mixtures use sodium nitrate instead of potassium nitrate, both salts. The source of carbon is charcoal, willow being historically the most popular. As the finer granulations of black powder burn faster due to more surface area per weight, the combustion speed was partially controlled by powder granulation size. You needed slower powder burns in those long barrels, a courser granulation was used, fast combustion and the finer grains where used to ensure complete combustion in the shorter barrels of handguns.
Muzzle Velocity of Black Powder
As the energy in black powder, the diminishing returns of increased charges, the muzzle velocity of black powder is from the extreme high of about 2000 feet per second (fps) down around 400 fps. Most guns will fall into the 1,100 to about 1,400 fps area. And with round balls the only way to increase the energy is to go to bigger bores, shooting larger balls. Take the .36 caliber “squirrel gun” probably shooting a .375 inch ball of 71 grains. Sectional density (SD) is 0.072, coefficient of drag(CD) is 0.470 and the ballistic coefficient (BC) is 0.153, not very good. The Kinetic energy (KE) at 1,300 fps is only 266.42 ft. lbs. a little weak but economical and good enough for small game, but not combat. Now look at the .69 caliber 495 grain ball. It has a SD of 0.149, CD = 0.470 and a BC of 0.316. At the same 1,300 fps we have a KE = 1,857.43 ft. lbs. of energy, big difference. The secondary projectiles caused by the mighty .69 caliber round ball hitting bone produced devastating and mortal injuries.
Rifled Barrel, Percussion Cap & Minie Ball
Smoothbore muskets could be loaded faster, with the British soldier doing about 3 rounds a minute, while the patched balls of rifled barrels were lucky to get two rounds off, and that starting with a loaded gun. But the rifled barrel could reach out effectively to 200-300 yards, making it a fine snipping and skirmishing weapon for precision hit and run attacks of the Patriots versus the British. Then about the mid-nineteenth century two changes cause a dramatic change, the percussion cap and the Minie ball. Most countries where converting to the percussion cap, it worked better in damp conditions, had a faster lock time making shots more accurate and sped up the loading process. Claude Minie of the French Army invented an elongated projectile with a hollow base. This allowed for faster reloading and the skirts at the base of the bullet would expand engaging the rifling and made for accurate shots out to an easy 300 yards with the reloading speed of the musket. The percussion rifle and the Minie ball dominated the battle in the American Civil War and the Crimean War. However, Napoleonic tactics that the officers of both the North and South were trained in governed warfare leading to very high casualties. Breach loaders improved loading from a prone, protected position at an even higher rate of fire, making the Shapes the choice of snipers and sharpshooters as well as the cavalry using the carbine version. The cavalry however embraced the cartridge firing repeating Spencer and the lucky few armed with Henry’s with 15 rounds. Considered the first modern war, the Civil War was chilling in the number of casualties but the slow evolution of tactics.