Rifled breech loader
From Wikipedia, the free encyclopedia
A rifled breech loader (RBL) is a large artillery piece which, unlike the smooth-bore cannon and rifled muzzle loader (RML) which preceded it, has rifling in the barrel and is loaded from the breech at the rear of the gun.
The spin imparted by the gun's rifling gives projectiles directional stability and greater penetrating power. Loading from the rear of the gun leaves the crew less exposed to enemy fire, allows smaller gun emplacements or turrets, and allows a faster rate of fire.
[edit] History
The very first cannon of the Middle Ages were breech loaded, with gunpowder and shot contained in pots dropped at the back of the barrel, but the poor seals made them dangerous, and they wore quickly and could not be scaled to larger weapons. Muzzle-loaders were then used until the 19th century.
In 1837 Martin von Wahrendorff patented a breech-loader with a cylindrical breech plug secured by a horizontal wedge; it was adopted by Sweden in 1854.
Whitworth and Armstrong introduced improved designs in the 1850s and 1860s which were adopted by the British Army, but concerns about armour penetration of the shells and wear rates led the British Government to revert to the rifled muzzle-loader in 1870. Only when the interrupted screw appeared was the superiority of RBLs acknowledged.
The Imperial Japanese Army used Armstrong cannon during the Boshin War to devastate the Aizu castle town and force its inhabitants to surrender quickly.
These new guns led to an arms race in fortification and ironclad warship design that lead to the battleship class of HMS Dreadnought and continued until the start of World War I.
