Re: Newbie question: Carbine vs. Rifle
Regarding the statement "The reason many people associate carbines with a pistol cartridge is because of the M1 Carbine issued to US troops during WWII "...
The .30 Carbine round (7.62 x 33) was NOT a pistol cartridge. It was a .30 caliber rimless version of the Winchester .32 self-loading rifle cartridge, designed for use in the Winchester Model 1905. Granted the round has straight walls, no shoulder, and a round nosed projectile like pistol cartridges, and Ruger built a revolver that could chamber the round, but it started out as a rifle round, not a pistol round, and few pistols were chambered for it.
In many ways the .30 Carbine was the first "assault rifle", but the round it fired was a bit anemic by modern standards. Had it chambered a decent round, it might have been the first true assault rifle. It had essentially every other characteristic of what we now call an assault rifle.