The rifle became a magazine loader, and it will next be an automatic loader (though at present automatic loading is principally used in machine guns and low-power rifles).
The pistol, instead of becoming a magazine loader (in the sense of being loaded by cartridges brought up from a magazine by operating a bolt), became a revolver—that is, the cartridges were fired out of the magazine instead of being first inserted into the barrel from a magazine.
When cartridges are inserted into the barrel, there is no escape of gas at the breech when they are fired, but when fired out of the cylinder of a revolver, there is an escape of gas at the juncture of the cylinder and barrel, which varies, and when such escape of gas occurs it causes weak and low shots.
The cylinder cannot be made gas tight, as that would prevent its revolving, or coincide absolutely with the calibre of the barrel, consequently a revolver can never be as accurate as a single-shot pistol.
This defect in the revolver was its weak point in comparison with the magazine-loading rifle.
Just before the war, I shot two makes of military full-charge automatic rifles, which were very good, but the war has put an end to their development for the present. Undoubtedly the rifle of the future will be an automatic.
The principle of an automatic firearm can be best explained by the analogy of the automobile.
The revolver, which is a magazine pistol, can be fired only after each cartridge is placed in position by the action of cocking the hammer with the thumb, or by double-action trigger pull.
The internal combustion (the automobile engine) operates by the explosion operating the various parts.
The explosion in the cylinder of the engine drives the piston rod forward, which turns the crank, which, turning the fly-wheel, drives the piston rod back ready for the next explosion.