[Yo-Yo]

I believe the idea of having more smaller/lighter rounds started with Kalishnikov, and was defining characteristic of the “assault rifle”.

WWII Germany and the Sturmgewehr 44 was the first Assault Rifle.

The defining characteristic was a new medium cartridge that fell between a rifle cartridge and a pistol cartridge.

[Joe 6-pack]

"WWII Germany and the Sturmgewehr 44 was the first Assault Rifle....The defining characteristic was a new medium cartridge that fell between a rifle cartridge and a pistol cartridge."

There are some amongst us that would argue the concept was a genuinely American one...granted the Germans coined the term Sturmgeweher and the weapons were designed for two very different roles, but when it came to actual battlefield usage, there really wasn't much difference...

[Perdogg]

Actually the Russians used the PPsh submachine gun first.