Technically you are right by virtue it uses a 45ACP, but that would be the same as saying any assault rifle using a pistol round cannot be called thus like the Uzi or an MP40.
If the firearm is capable of full-auto fire, and is chambered for a pistol round, it's a sub-machine gun. (The Germans referred to them as a "Maschinenpistole" or "machine pistol", which is where the "MP" in "MP-40" comes from).
The definition of "assault rifle" comes from the Sturmgewehr 44: a selective-fire rifle chambered for a rifle cartridge of reduced size and/or power.
“Technically you are right by virtue it uses a 45ACP, but that would be the same as saying any assault rifle using a pistol round cannot be called thus like the Uzi or an MP40.”
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The original “assault rifle”, i.e. “sturmgewehr 43/44” did not use a pistol cartridge nor a full-sized rifle cartridge...it used a modifieid cartridge, i.e. the 8mm “Kurz” or “short round”.
I suppose to gun grabbers, any firearms that sounds like “rat-tat-tat-tat-tat” or “budda-duh, budda-duh” (Sorry, SGT FURY fans), they’re all the same.
Technically all those (the Thompson, the Uzi, and the MP40) were classified as machine pistols, or submachineguns, because they were all chambered in pistol cartridges...
the infowarrior