Modern mass production firearms are breech-loading (though mortars are generally muzzle-loaded). Early firearms were almost entirely muzzle-loading. The main advantage of breech-loading is a reduction in reloading time—it is much quicker to load the projectile and charge into the breech than to force them down a long tube, especially when the tube has spiral ridges from rifling. In field artillery, breech loading allows the crew to reload the weapon without exposing themselves to enemy fire or repositioning the piece (as was required for muzzle-loaded weapons) and allows turrets and emplacements to be smaller (since breech loaded weapons do not need to be retracted for loading).
Although breech-loading weapons were developed as far back as the late 14th century in Burgundy, breech-loading became more successful with improvements in precision engineering and machining in the 19th century.
The main challenge for developers of breech-loading weapons was sealing the breech. This was eventually solved for smaller weapons by the development of the self-contained metallic cartridge. For weapons too large to use cartridges, the problem was solved by the development of the interrupted screw.
Swivel guns 
Breech-loading swivel guns were invented in the 14th century. They were a particular type of swivel gun, and consisted in a small breech-loading cannon equipped with a swivel for easy rotation, and which could be loaded by inserting a mug-shaped chamber already filled with powder and projectiles. The breech-loading swivel gun had a high rate of fire, and was especially effective in anti-personnel roles.
More breech-loading firearms were made in the early 18th century. One such weapon is known to have belonged to Philip V of Spain, and was manufactured circa 1715, probably in Madrid. It came with a ready-to load reusable cartridge.
Patrick Ferguson, a British Army officer, developed in 1772 the Ferguson rifle, a breech-loading flintlock weapon. Roughly two hundred of the rifles were manufactured and used in the Battle of Brandywine, during the American Revolutionary War, but shortly after they were retired and replaced with the standard Brown Bess musket.
Later on into the mid-19th century there were attempts in Europe at an effective breech-loader. There were concentrated attempts at improved cartridges and methods of ignition.
In Paris in 1808, in association with French gunsmith François Prélat, Jean Samuel Pauly created the first fully self-contained cartridges: the cartridges incorporated a copper base with integrated mercury fulminate primer powder (the major innovation of Pauly), a paper casing and a round bullet The cartridge was loaded through the breech and fired with a needle. The needle-activated central-fire breech-loading gun would become a major feature of firearms thereafter. The corresponding firearm was also developed by Pauly. Pauly made an improved version, which was protected by a patent on 29 September 1812. The cartridge was further improved by the French gunsmith Casimir Lefaucheux in 1836.
The low-powered copper Flobert cartridge was invented in 1836, as was the pinfire cartridge (Lefaucheux), although this required fixative work by Houiller in 1846 to produce a workable cartridge. The rimfire cartridge was introduced in the 1850s, and centrefire cartridge in 1857 by Pottet, with both Berdan and Boxer priming.
In 1842, the Norwegian Armed Forces adopted the breechloading caplock, the Kammerlader, one of the first instances in which a modern army widely adopted a breechloading rifle as its main infantry firearm.
The Dreyse Zündnadelgewehr or Dreyse needle gun, was a single-shot breech-loading rifle using a rotating bolt to seal the breech. It was so called because of its .5-inch needle-like firing pin, which passed through a paper cartridge case to impact a percussion cap at the bullet base. It began development in the 1830s under von Dreyse and eventually an improved version of it was adopted by Prussia in the late 1840s. The paper cartridge and the gun had numerous deficiencies; specifically, serious problems with gas leaking. However, the rifle was used to great success in the Prussian army in the Austro-Prussian war of 1866. This, and the Franco-Prussian war of 1870–71, eventually caused much interest in Europe for breech loaders and the Prussian military system in general.
In 1860 the New Zealand government, fearing that the British government would not supply regular troops to protect citizens from a threatening Maori rebellion, made inquiries to Britain to obtain modern weapons. In 1861 they placed orders for the Calisher and Terry Carbine, which used a breech loading system using a bullet consisting of a standard Minie lead bullet in .54 calibre backed by a charge and tallowed wad, wrapped in nitrated paper to keep it waterproof. The carbine had been issued in small numbers to English cavalry(Hussars) from 1857. About 3–4,000 carbines were brought into New Zealand a few years later. The carbine was used extensively by the Forest Rangers( a small special forces unit who had elite training in bush[NZ jungle] fighting) lead by the Prussian aristocrat Ferdinand von Tempsky. This was a small elite unit that operated as a reconnaissance unit that often spear headed attacks against Maori rebels. Von Tempsky liked the short carbine, which could be loaded while lying down. The waterproofed cartridge was easier to keep dry in the wet New Zealand bush ( dense jungle). Late in the 1860s the New Zealand Government had about 1800 carbines issued or in storage. It is believed by researchers that the balance were sold to private citizens and militia during the Rebel Maori uprising from 1863. Museums in New Zealand hold a small number of these carbines in good condition. At least one New Zealand example, fully carved in tradition Maori style, was sold in recent times in the UK. It is not known if this weapon was used by Maori troops fighting for von Tempsky or if it was a captured weapon or one of the carbines sold to private citizens.
During the American Civil War many breech loaders would be fielded. The Sharps used a successful dropping block design. The Greene used rotating bolt-action, and was fed from the breech. The Spencer, which used lever-actuated bolt-action, was fed from a seven-round detachable tube magazine. The Henry and Volcanic used rimfire metallic cartridges fed from a tube magazine under the barrel. These held a significant advantage over muzzle-loaders. The improvements in breech-loaders had spelled the end of muzzle-loaders. To make use of the enormous number of war surplus muzzle-loaders, the Allin conversion Springfield was adopted in 1866. General Burnside invented a breech-loading rifle before the war.
The French adopted the new Chassepot rifle in 1866, which was much improved over the Needle gun as it had dramatically fewer gas leaks due to its de Bange sealing system. The British initially took the existing Enfield and fitted it with a Snider breech action (solid block, hinged parallel to the barrel) firing the Boxer cartridge. Following a competitive examination of 104 guns in 1866, the British decided to adopt the Peabody-derived Martini-Henry with trap-door loading in 1871.
Single-shot breech-loaders would be used throughout the latter half of 19th century, but they were slowly replaced by various designs for repeating rifles, first used—and heavily—in the American Civil War. Manual breech-loaders gave way to manual magazine feed and then to self-loading rifles.
The first modern breech-loading rifled gun is a breech-loader invented by Martin von Wahrendorff with a cylindrical breech plug secured by a horizontal wedge in 1837. In the 1850s and 1860s, Whitworth and Armstrong invented improved breech loading artillery.
See also 
- Tower of London exhibit.
- Musée de l'Armée exhibit, Paris.
- Chemical Analysis of Firearms, Ammunition, and Gunshot Residue by James Smyth Wallace, p. 24 
- Firearms by Roger Pauly p. 94
- A History of Firearms by W. Y. Carman p. 121
- Te Awamutu Museum, Te Awamutu, Waikato, New Zealand. Research notes and a C and T carbine
- The History of Russian Artillery since the mid-19th century up to 1917
- "Breech Loading Rifled Artillery". Global Security. Retrieved 2009-02-25.
- "History of the Rifled Cannon: Discovery of the Breech-Loading Gun and Conical Projectiles". The New York Times. July 12, 1861. Retrieved 2009-02-25.
- An Illustrated History of Breech-Loading Guns. Scientific American past. 6/2/1894.