We do have firearms that are legally classified as "weapons of war" over here in France, mostly fully automatic small arms.
The list also includes gaz masks, IR and night vision optics and other things.
In some countries it also includes weapons of any caliber used by the military.
That's why .380 pistols are popular in some European countries where citizens can't own guns chambered in "NATO 9mm" (9x21mm).
You can pretty much include anything you want in the "weapons of war" categorie.
In some US states any rifle with a magazine capacity over 20 or more rounds already turns a legal semi-auto rifle into an illegal "assault weapon".
A "common sense ban on weapons of war" would be the end of the second amendment as it could include virtually anything.
My Dad has a no-kidding "weapon of war". It's an 1898 Springfield chambered in .30-40 Krag. It was manufactured in 1901 and in 1901 it was the issue weapon to the US armed forces. Weapons like this wee used by US forces in the Spanish-American War. It's bolt action and has a 5 round internal magazine loaded from the side. My semi automatic AR-15 has never been used in war by any country.