With a background in designing artillery projectiles and systems of firing, Hotchkiss formulated what he considered to be the best caliber to produce the most destructive force capable from a rapid firing weapon. The result of his calculations was a bursting charge cavity of correct dimensions and a balanced fuzed nose with a 37mm projectile. The gun he built around the 37mm round was intended for flank defense and he introduced a new and unique feature. Each of the five barrels was rifled with a different pitch ensuring a sweep of the target area with shrapnel.
While the Hotchkiss Revolving Cannon, on first impression, resembles a Gatling gun, it is operationally markedly different. The five barrels are mounted parallel to each other around a central shaft and are rotated and controlled by means of a hand crank that also controls the loading, firing and extracting operation. Unique to the Hotchkiss internally is that the barrels are rotated intermittently without turning the breech mechanism. Thus, the barrels are stationary at the moment of firing negating any centrifugal force normally imparted to projectiles at the start of their flight when fired from a continuously rotating barrel. Additionally, there was just one firing pin and spring instead of five and a single loading piston. This enabled the parts to be made stronger and heavier to withstand the shock from such a large caliber round. Another unique feature was that the gun was so designed that it could be disassembled and assembled without the use of any tools. The gravity feed system also employed another exclusive feature to prevent the problems encountered in other machine gun systems that employed a system of stacking rounds one on top another in the feed chute. As the loading piston moves forward loading a round, a gate rises and isolates the round being loaded from the other rounds on top of it in the feed chute providing even spacing of the rounds preventing feed jams.
The impressive 37mm round contained 3.5 ounces of powder. The cartridge case measured 3.66 inches without projectile, 6.68 inches long with projectile, and a complete round weighed 2.42 pounds.
There were six models of the manually operated Hotchkiss Revolving Cannon depending on their specialized purpose: the light 37mm for field use; a high velocity 37mm for flank defense and fortifications; the 37mm designed for shipboard use only; a 40mm for fortifications; a 47mm gun for naval use; and a 57mm gun, also for naval use.
At one time or another, the Hotchkiss Revolving Cannon was used by just about every navy in the world including Germany, England, Holland, Italy Austria, Turkey, Denmark, Russia and the United States. The French Navy alone used over 10,000 revolving cannon and four million rounds of ammunition.
Gardner Battery Gun
The inventor of the Gardner Battery Gun was William P. Gardner, born in Marietta, Ohio in 1843. After the American Civil War, serving with the 9th Ohio Volunteer Calvary, Gardner had a varied career as a customs inspector, an architect, and an inventor. Working from previously conceived design sketches, he constructed the first wooden prototype in 1874 and, with the aid of a Mr. Beckman, worked out later in the year the first operational metal prototype. In the following year, arrangements were made with the Pratt & Whitney Company to develop and manufacture the Gardner gun to meet military requirements.
After tests of the first single barrel gun to the Navy Ordnance Board in 1875, it was suggested that Pratt & Whitney (P&W) be allowed to take the weapon back to their factory to be perfected with the new feed system invented by E.G. Parkhurst. P&W had obtained the manufacturing rights for the Gardner Gun by paying the inventor a royalty on each gun delivered. They also controlled the Parkhurst patents for the improved model.
Gardner, who saw no orders from the US Government and his gun being drastically modified by P&W, sought to form a company to manufacture his patent gun. With a number of partners, the Gardner Gun Company was formed in August, 1879 whose purpose was to manufacture Gardner Patent Guns.
The company sent its Director and agent to Europe to submit the Gardner Patent Gun to different governments. Advised that the British War Office would be interested if the weapon was made in England, arrangements were made to have several Gardner Guns made in Leeds.
The British Admiralty first tested the Gardner gun, chambered for the .45 caliber Martini-Henry cartridge in February, 1880. The British War Office conducted another set of trials along with the Gatling, Nordenfelt and P&W’s Improved Gardner Gun in March, 1881. The trials resulted in the Gardner Patent system being judged best and the two-barrel Gardner as the most perfect form of the system. In anticipation of receiving orders from both the British Army and the Admiralty, a factory and office were established in London.
The Gardner gun consisted of two breech-loading barrels placed parallel to each other and fastened at the breech end and housed in a single casing. They were loaded, fired and ejected alternately by one complete revolution of the crank handle. Feeding was accomplished with two vertical T-slot feed guides that dropped the loaded cartridges in correct position for the feed entrance. The body of the crank shaft is circular in construction and has crank pins for operating the bolts. These pins are diametrically opposite each other for alternate firing sequence. As one bolt closes on the chamber of one barrel for firing, the other bolt is being withdrawn with the spent cartridge case for ejection. Thus, as the crank handle is turned, the barrels fire left, right, left, right alternately.
An official report on the working of the Gardner gun mechanism stated that it possesses every quality desirable in a machine gun, namely: lightness, strength, simplicity and durability; all working parts readily accessible; prospects of a feed that positively aligned the incoming rounds independently for each barrel; and an adaptation for firing each barrel at will.
Improvements by both Pratt & Whitney and the Gardner Gun Company were patented in subsequent years refining, feeding, firing, extracting and ejecting for single barrel models, 2-barrel models and 5-barrel models, as well as improvements on tripods, mounting and traverse and elevation mechanisms. Succeeding 2-barrel models had an enclosed water chamber that surrounded the barrels for cooling purposes, open at the top to allow filling and steam to escape and a valve underneath to allow draining.
The Gardner Gun Company and Pratt & Whitney were competitors with essentially two different guns under the Gardner name, vying for international patents and international sales, with ultimately Pratt & Whitney being the survivor of the two with the Gardner Gun Company going out of business in 1895. Nevertheless, the Gardner Battery Gun, second only to the Gatling, was produced in greater quantities than the Nordenfelt or others of the period. It was adopted by five countries, tested by an additional four countries, and was manufactured in three countries.
Nordenfelt Machine Gun
The last of the major players in the rapid fire, manually operated, machine gun race of the era was the Nordenfelt machine gun. Heldge Palmcrantz, a Swedish engineer, perfected probably the best attempt at a battery gun. His mechanism of locking and firing was realized by the fore and aft movement of a single operating lever that allowed the gunner to sustain fire or discharge the barrels one at a time. A separate framed gravity feed system was positioned over each barrel and allowed the cartridges to drop through openings in the frame after the empty brass has been extracted.
So why isn’t this gun called the Palmcrantz gun? As is often the case with inventors, they have no funds to see the fruition of their ideas and need monetary backing for their ideas to become a reality. So it was that Palmcrantz approached a Swedish broker by the name of Thorsten Nordenfelt to finance his project. Nordenfelt, at the time conducting banking business in London, agreed but under the condition that thereafter the name was to be the Nordenfelt machine gun.
Nordenfelt was not only a shrewd business man; he was one of the world’s greatest salesmen of his day. Taking a design that was obsolete from the beginning, he successfully promoted a multibarrel battery gun that was inferior to half a dozen other guns available at the time. Being well-connected, and wishing to satisfy the whims of people who would buy his product, he offered his gun in 1- to 12-barrel versions in any caliber from rifle cartridge to artillery.
The English Government’s Small Bore Machine Gun Committee in 1880 laid down three basic conditions that had to be met before a machine gun could qualify as being worthy of consideration.
- It must be capable of firing 400 rounds per minute.
- The breech of the barrel being fired to remain securely closed one third of a second, or ample time in the opinion of the experimental committee to insure safety from a delayed explosion of a cartridge case (hang fire).
- To fire rapidly 1,000 continuous rounds at a speed satisfactory to the committee. That must not cause undue heating of the barrels.
These conditions were easily met by the Palmcrantz system and exploited by Nordenfelt. He typically used a 12-barrel gun for the trials that could easily fire 400 shots per minute, or less than 50 shots per barrel. A 1,000 round burst is only about 83 shots per barrel eliminating the overheating problem. In one trial in Portsmouth, England in 1882, Nordenfelt used a 10 barrel rifle caliber gun that fired an astonishing 3,000 rounds in 3 minutes and 3 seconds without a parts failure or stoppage. Though an outdated design the workmanship, reliability, and endurance of his gun was extraordinary. The only real drawback operationally in the Nordenfelt gun was that it was not possible to ascertain visually whether the gun was loaded or not.
In all, there were 18 models of his multibarrel battery gun. The British Admiralty were impressed with its performance and reliability and bought a number of the .45 caliber 5-barrel models and 1-inch 3-barrel models. A number of other European navies purchased the Nordenfelt gun as well and it was quite poplar throughout Europe.
It should be noted that it was not the British Army but the British Navy who was exceptionally keen on machine guns and purchased and used large quantities of Gatlings, Gardners and Nordenfelts to great effect.
The final battery gun to be briefly discussed here is the .450 caliber Bira gun. It was not a player in the international scene, but was locally produced in Nepal for the Nepalese army and was the last of its type to be developed and used.
Designed by Gehendra Shamsher Jang Bahadur Rana, the massive Bira gun was operationally based on the Gardner gun except for the pan magazine and feed mechanism. The gun was named in honor of King Prithvi Bir Bikram Shah. It is estimated that no more than fifty were made and, historically important to museums and collectors, a small number have been discovered and will soon be available.
With the perfection of the battery gun came the tactical question of how to best employ it in battle. In a group of their own, they were neither an individual soldier’s firearm nor a piece of artillery. Most early depictions show battery guns mounted on wheeled carriages resembling a piece of artillery. As they were worked by cranks and levers, this required the guns to be mounted on heavy carriages, so that the motions of the operator would not be transmitted to the gun, and for the same reason necessitated the use of elevating screws and toggles for pointing. The range of fire for the rifle caliber battery gun was between that of the individual soldier and that of an artillery piece, being between 800 to 1,200 yards.
Many early tacticians believed this range to be ideal, but did not know where or how to employ the battery gun for its best utilization. Few envisioned that it was a close support weapon being wheeled forward with the attacking troops, while others felt it should be with the artillery as a support weapon to defend the artillery battery from attack, freeing up the valuable infantry to fight elsewhere. In the employment with the artillery, the battery gun’s description as “Rifle Caliber Artillery” becomes appropriate.
The most widely know battery gun in the U.S. service, and in many other countries around the world, is the Gatling gun. It is to be considered the premier battery gun as it was produced and used in greater quantities and manufactured in more countries than its competitors. The Gatling was without rival until the latter part of the 1870s, when the Nordenfelt and Gardner battery guns began competing against it, but the Gatling never lost its lead until the advent of the truly automatic machine gun invented by Hiram Maxim.