Click here for a pretty succinct history of the rifle. The flintlock appears to be the rifle of choice and necessity in the 1700's.
There are two types of flintlock rifles applicable to the 1700's: the Brown Bess (pictured above) and the Kentucky Rifle (pictured below).
About the Brown Bess: "The first truly famous, or perhaps infamous, gun in history was a flintlock, the "Brown Bess." The British actively employed the Brown Bess during the American War for Independence, the French and Indian War, and the War of 1812. However, Brown Besses still ended up in the hands of American militiamen in the Mexican War and even in the American Civil War! The Brown Bess still had no provision for aiming, but its weight had been reduced to around 8lbs. This allowed quick firing by most soldiers in the range of three shots per minute."
Info on the flintlock known as "The Kentucky Rifle" and a photo follow:
Surprisingly, one of America's earliest triumphs in artistic and functional design, the "Kentucky rifle," was not invented or generally fashioned in Kentucky. The name was coined from a hearty stock of Americans who plied it.
Native Americans called Kentucky the "Dark and Bloody Ground" because of the unending wars between Iroquois and Cherokees for its possession. New worlders thought of the first wild west as a hunter's paradise. In 1752, a stalwart American Indian trader named John Findley, traveled the Ohio River documenting the valley's beauty and abundance. In 1769, a bold young explorer and skilled marksman, who was given an American-made flintlock rifle at the age of twelve, hired Findley and four other woodsmen to guide him through a wilderness country road between Kentucky and Tennessee which is now know as the "Cumberland Gap." In 1775, (Daniel) Boonesborough, Kentucky was established.
During the Revolution, demoralized English officers wrote home about a new type of American-made long-barreled "rifle" backwoodsmen used with astonishing skill. When the war was won, the new government paid debts to its officers by offering land grants in untamed land. Claiming their acreage, these adventurers brought their rifles to Kentucky with them.
Near the end of the lost War of 1812, American spirits were raised when five thousand Americans, including two-thousand frontiersmen with long barreled guns, under the command of General Andrew Jackson, defeated the British in the Battle of New Orleans. A popular song called "The Hunters of Kentucky or The Battle of New Orleans" (no doubt, written by a proud Kentuckian) forever named America's rifle.
"But Jackson he was wide awake, and wasn't scar'd at trifles, for well he knew what aim we take, with our Kentucky Rifles."
The Kentucky rifle was invented and predominantly made in Pennsylvania. A good shooter cost half a man's yearly wage. Most were used for hunting on a daily basis. They were handed down from generation to generation, and are often found in worn condition today. Antique dealers like myself call this "patina" and charge additional fare for it. Many of the early "flintlock" rifles were converted to the improved "percussion" system in the 1830's. This does not ruin the value of a Kentucky rifle. It is simply a chapter of its life.
Age, artistic beauty, and condition are the most important factors in gauging the value of the world's most sought-after firearm. A classic specimen is stocked in native American tiger stripe maple. (Dealers note* Tiger maple is almost never found in European furniture and thus is evidence of valuable American origin.) A rare colonial "transition era (1715-1775)" flintlock specimen in a plain grain of maple, walnut, cherry, or birch, can command a huge sum. Keep in mind, most plain-wood Kentucky rifles found today were made during the third generation "percussion era.(1825-1860)" These are generally, thousand dollar rifles, not five figure antiques.
Pictured above from www.flayderman.com is a CLASSIC EXAMPLE OF THE “GOLDEN AGE” KENTUCKY RIFLE BY A FAMED MAKER, CIRCA 1780-1790
"Original flintlock. Although unsigned (as are a great many Kentucky rifles) this fine early American longarm typifies the work of Wolfgang Haga, of Berks County, Penna. (died 1796), among the very earliest of Kentucky rifle makers. The brass mountings and patch box and a toe plate identical to those found on most Haga rifles (and exactly as shown on pages 200-202 of classic work on the subject “Thoughts on the Kentucky Rifle in its Golden Age” by Kindig, 1960). An excellent example of an 18’th century specimen of this historic American rifle in lovely condition by one of the earliest makers."