Claims of the first "assault rifle" are many, but most consider the German Stg-44 the first modern select-fire infantry weapon. However, a few decades before World War II a Russian weapons designer Vladamir Fedorov successfully created a weapon that vies for the title of first, if not as refined.
The Avtomat was a mix of modern assault rifle attributes, lingering 19th century aesthetics and reduced power ammunition. The rifle could fire on full-auto and initially was designed in 1911 with the standard Russian 7.62 x 54R rifle cartridge. A rimmed ammunition, the base having a flange of metal as compared to other cases which base rim is flush, the 7.2x54R was a full-powered caliber.
Realizing this was too much for the new design, Fedorov created a proprietary 6.5mm class of ammunition that reduced the size, weight and recoil forces. These first rifles had a fixed magazine and were fed by a stripper clip. Eventually, Fedorov designed a removable magazine that held 25-rounds of his 6.5mm ammunition.
The method of operation of the Avtomat is unusal for shoulder fired weapon. The mechanism was comprised of three main operating parts, the barrel, bolt and locking plates.
A pair of h-shaped steel plates were fixed to the breach end of the Avtomat's barrel. The plates were attached to the barrel by a pair of pivot pins. The barrel was not married to the receiver like most rifles, instead it recoiled freely. As propellant gases expanded, the barrel recoiled back and the pair of plates, mounted vertically, slid back several milimeters. The plates then tilted downward and engaged lugs in the rifle receiver.
The locked up plates would hold the barrel in its rearward movement. This would then allow the bolt body to recoil back further, ejecting a round and recoiling forward again to strip a fresh from the magazine.
The rifle's refinement came to a halt with the start of World War I. Since the Avtomat was essentially nearing completion, it was decided to change the caliber into something existing, more plentiful and easily produced. The Japanese 6.5mm Arisaka was the natural choice for the new Avtomat, as it closely resembled the performance of the proprietary Fedorov ammunition and required minimal changes to the rifles already produced.
Several thousand Avtomat rifles were produced by Russia through the early 1920s and examples of the rifle fought on through World War II.
A footnote in small-arms history, the Avtomat should not be overlooked as an example of a true early assault rifle.