'Lock, stock and barrel' comes from the three main parts of a musket
The phrase lock, stock and barrel names a musket's firing mechanism, wooden body and tube. The weapon itself began around 1521 as an arquebus so heavy it rested on a forked stick, built to punch through plate armour, and its very name may trace back to a sparrowhawk.
One theory links musket to the French mousquette, a male sparrowhawk, since firearms were often named after animals; another points to the Italian moschetto, a crossbow bolt, from mosca, a fly. The word appears in Europe in 1499, though historian David A. Parrot suggests the musket may have been little more than a new name for a heavier arquebus. At the 1521 siege of Parma, Spanish troops reportedly used such an arquebus with rest.
Firearms drove an arms race. Armour thickened from 15 kilograms in the 15th century to 25 in the late 16th, since plate 2 millimetres thick took nearly three times the energy to pierce as 1-millimetre plate. Eventually musketeers became the first infantry to abandon armour entirely, sheltering behind walls and skirmishing, and English barrels were shortened from 4 feet to 3 around 1630. A smoothbore musket could hit a 50-centimetre target at 100 metres, and its ball could fly as far as 1,100 metres.
Firing mechanisms moved from matchlock and wheel lock to flintlock and finally percussion caps, although China and Japan kept matchlocks until percussion arrived. Refinements came in 1750 with a detent to stop the sear catching at half-cock, in 1770 with a roller bearing for better sparks, and in 1780 with waterproof pans. Paper cartridges held pre-measured powder and ball: the soldier tore one open, primed the pan, poured the rest down the barrel and rammed it home. Ramrod attachments included a screw for pulling jammed balls, much like a corkscrew.
Claude-Étienne Minié's bullet-shaped Minié ball, with a skirt that expanded to grip rifling, let rifled muskets reach combat ranges around 300 yards in the American Civil War. Breech-loading cartridges, introduced by Casimir Lefaucheux in 1835, and the Henry rifle of 1860 and Winchester of 1866 finished the musket off.
Source: Musket
