These early reusable steel cartridges tubes led to problems with gas leakage but despite these problems the gun was reportedly able to fire up to 200 rounds per minute.

58 calibre paper cartridges and percussion caps contained within what Gatling described as ‘cartridge chambers’ these self contained metal tubes held powder, percussion cap and projectile. The cartridge fired by the gun went through a rapid evolution through separate. The first model Gatling Gun fed from a hopper which had been used on the earlier Agar ‘coffee mill’ Gun. Gatling was granted a patent for the ‘Improvement in revolving battery-guns’ on the 4th November, 1862 (see image #7). This linear diagram from 1878 shows how the Gatling’s action worked with the bolts moved by the spiraled cam which loaded, fired and extracted the ammunition ( source) This high rate of sustained fire was made possible by the Gatling’s numerous barrels, each barrel once fired had time to allow heat to dissipate unlike a conventional single barrel machine gun. Early models were capable of up to 200 round per minute but later models were able to fire much faster with rates ranging between 700 to 1,000 round per minute - the upper limit of a manually loaded and cranked action. This process meant that each barrel was fired with one turn of the crank. The fired barrel then continued to travel clockwise and the spent case is pulled from the breech by the bolt which is being retracted by the spiralled cam. When the barrel reached the 6 o’clock position of the cycle its firing pin was tripped by the movement of the barrel’s cammed lock firing the gun. As the gun’s crank was rotated the action was cycled with the barrels turning through 360-degrees, each barrel had a cammed lock/bolt which fed the cartridges. Ammunition fed in from the top of the receiver with a single cartridge being loaded into each chamber. The weapon had six to ten barrels each with its own bolt, firing pin and extractor with each barrel firing in sequence. The basic design of Gatling’s gun was refined over its 40 year lifespan but the basic operation remained the same. Famously inspired by Gatling’s hope to minimise the number of men needed to fight during the US Civil War, this flawed logic lead to a weapon which would be used throughout the world until it was finally surpassed in the 1890s by the Maxim Gun - a fully-automatic machine gun. With a number of barrels arrayed around a central axis and a top loading magazine which loaded each barrel in turn before the continuing turn of the guns crank fired the weapon. Cycled by the operator the weapon’s rate of fire was limited only by the speed of which it could be operated. Invented by Dr Richard Gatling in 1861 the Gatling Gun is the most famous of all manual machine guns.

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