Electric Cannon Uses No Gunpowder (June 1932)
Source: Modern Mechanix
SILENT guns sending their whistling messengers of death into the sky at speeds far beyond those now attained by powder-driven shells seem likely for the next war, using for propulsion magnetic fields so powerful that when they are short-circuited they produce miniature earthquakes.
Dr. Kapitza, F. R. S., working at the Cavendish laboratory of
Another English experimenter, Dr. Wall, seeking the same thing, produces ultra-magnetic fields with a more simple apparatus. Dr. Wall simply charges electrostatic condensers and permits them to discharge their powerful currents into specially made coils immersed in oil baths. Here also magnetic fields so powerful that they tear the coils to pieces have been produced. So great are these magnetic fields that they are capable of pulling iron nails out of shoes.
While the magnetic effects produced by both of these experimenters are of very short duration, they could be employed to impart their terrible energy to steel shells. The time limit, which cannot exceed one one-hundredth of a second, is imposed because of the powerful currents used. If these currents were permitted to flow through wire for a greater period of time, the wire would melt and temperatures greater than those existing in some of the hottest stars would be produced.
To produce a magnetic gunÃ¢ï¿½ï¿½a silent Big-BerthaÃ¢ï¿½ï¿½it will only be necessary to arrange a series of powerful coils within the gun barrel. Each coil will have its own generator and the shell advancing through the barrel will automatically energize the coil just ahead of it. By the time the shell reaches the end of the barrel it will have attained a speed far in excess of the speeds now attainable with even the highest explosives known.
Owing to the entire absence of internal pressures these guns may be made of ordinary iron or even of purely non-magnetic materials. The Ã¢ï¿½ï¿½magnetic explosionsÃ¢ï¿½ï¿½ will be initiated by the simple closing of a switch which will energize the first: coil and snatch the shell from the breech in the first leg of its journey of destruction.
Source: Modern Mechanix 9-1934
The potential and power of launching a projectile using electro-magnetic force have fascinated inventors and researchers ever since the solenoid was invented. However, none of the attempts was successful. During World War II
THE ELECTRIC GUN
German Experiment With Electrically Launched Projectiles
Although the gun ordered was not delivered before the end of the war, a miniature that actually worked was built and tested. Theoretical calculations, based upon tests made with the miniature gun, led the German scientists to believe it possible to build an electric gun capable of tossing a 14-pound projectile to an altitude of 12 miles in 13 seconds.
Although the problem of electrically ejected shells is an old one, it has still to pass the research stages. The chief problem is to obtain a source of sufficient electrical power that will not be all out of proportion to the size of the gun. Designing a gun did not seem to be too great a problem, for the German model appeared logical.
The German gun, had it ever been built to full scale, would have had a rectangular barrel 33.7 feet long. The round bore, as designed by the Germans, is flanked by two, square grooves 180 degrees apart, so that when the bore is seen from one end, it is the same shape as the aircraft identification insignia used by the U.S. Army Air Forces. The bore is not rifled. At the extreme ends of the two grooves, an insulated, copper glide rail runs the entire length of the barrel. It is through these glide rails that the electrical energy is conducted for ejecting the shell.
The shell is a cylindrical projectile somewhat longer than the conventional artillery shell, and has four narrow fins at its base. It is fitted with a cradle, called a "glide wing," from which extend two studs which fit into the square grooves of the bore, and ride on the copper glide rails. After the shell has been placed in the gun, a jolt of electricity is shot into the weapon. The current, passing along the glide rails and through the glide wing, sets up an intense magnetic field. The reaction is such that the magnetic field and the current flow through the glide rails tend to repel each other. This, in effect, forces the projectile up the bore at an ever increasing velocity until, when it leaves the muzzle, it is traveling at a terrific rate of speed. This reaction is so fast that it is only a matter of a split second between the introduction of the current and the ejection of the shell from the gun.
It is the opinion of some scientists that the electric gun deserves further study and experimentation, since it contains, in theory at least, some marked advantages over the conventional antiaircraft artillery of the present day. It is theoretically capable of obtaining muzzle velocities far in excess of what to date has appeared possible for powder-burning weapons. It is noiseless, smokeless, and has no flash. Constructed of materials easily obtainable, it requires comparatively little high-precision machining. Unlike other artillery pieces, the machined surfaces are not subjected to high pressures and intense heat. Moving parts are few, and these can be greased. Recoil is negligible, and range can be adjusted by varying the electric current. The gun has a high efficiency, compared to ordinary pieces, since there is no energy wasted through heat and escaping gases, and the manufacture and handling of cartridges is eliminated. But perhaps most important is the fact that ranges and penetrating power now unattainable may be reached in the electric gun.
Of course, these advantages are in turn offset by the chief problemÃ¢ï¿½ï¿½power supplyÃ¢ï¿½ï¿½and a myriad of minor electrical wrinkles that would require straightening before a truly efficient gun could be produced. It is one thing to handle large amperages in a power house, and quite another to supply them to, and use them in, a comparatively small piece of machinery which, to be of full military value, must retain the essentials of mobility.