“Arms” in the late 18th Century 

The historical record detailing the weaponry available to late 18th century militaries and private citizens is quite clear and not disputable.  

For the purposes of the Second Amendment, as drafted in 1789 and ratified in 1791 and amplified by the 1792 Militia Act, the Founders were addressing the arms available to “the people” as part of the requirement that the free white men from age 18 to 45 be available to join a “well regulated militia” in order to sustain the “security of a free state”, notionally the one where “the people” resided. 

What were the “arms” to which the Founders were referring?  Present day military experts and historians have provided the relevant historical materials.

The Militia Act of May 8, 1792 provides the starting point,, and the National Park Service offers further useful detail.

The Militia Act directly describes the arms envisioned in the Bill of Rights 2nd Amendment text whose conceptual foundation is a “well regulated militia, necessary to the security of Free State”:

The Act states…that every citizen, so enrolled and notified, shall, within six months thereafter, provide himself with a good musket or firelock, a sufficient bayonet and belt, two spare flints, and a knapsack, a pouch, with a box therein, to contain not less than twenty four cartridges, suited to the bore of his musket or firelock, each cartridge to contain a proper quantity of powder and ball; or with a good rifle, knapsack, shot-pouch, and powder-horn, twenty balls suited to the bore of his rifle, and a quarter of a pound of powder; and shall appear so armed, accoutred and provided, when called out to exercise or into service, except, that when called out on company days to exercise only, he may appear without a knapsack.”

The National Park Service documents that “The flintlock musket was the most important weapon of the Revolutionary War. It represented the most advanced technological weapon of the 18th century. Muskets were smooth-bored, single-shot, muzzle-loading weapons. The standard rate of fire for infantrymen was three shots per minute. The rifle, although slower to load, was more accurate than the musket. However, riflemen were at great disadvantage in close-quarters fighting against disciplined infantry armed with muskets and bayonets. Cavalrymen and officers used pistols. Pistols were effective only at close range.”

Source: (https://www.nps.gov/museum/exhibits/revwar/guco/gucoweapons.html) 

One of the most common weapons from the Revolutionary War was the “Brown Bess”, a muzzle loading smoothbore musket. While it originated in Great Britain and was a British weapon it was the primary musket used by the Americans. The musket was used to fire a single shot ball, or a cluster style shot which fired multiple projectiles giving the weapon a “shotgun” effect. There were two variations of the Brown Bess: (1) Short Land Pattern: shorter, less bulky, less heavy and (2) Long Land Pattern: longer and more common than the Short Land Pattern.

(Source:  https://thehistoryjunkie.com/weapons-from-the-revolutionary-war/);

In addition, there were other single shot weapons: American made muskets, long rifles, French made “Charleville Muskets”, the Ferguson rifle: and the Pattern 1776 rifle.

Individual arms also included a range of single shot pistols, bayonets, knives, lances and similar weapons designed for close in and man to man combat, and, in individual private circumstances, self-defense.