Quote Originally Posted by Arkhios View Post
By my reading (and I read it several times over) Arcane Firearm doesn't specify a type of firearm, and it seems to me that it's not an actual weapon, capable of firing bullets, but rather what it actually is: a spellcasting focus. The "ammunition" used are the artificer spells cast through it. It works to an extent, sure, but it's not a weapon per se.

Archery Fighting Style gives +2 to Hit, but yeah. That'd work.

At first I thought that Eldritch Knight could be the answer because of "1/3 per level" progression for spellcasting, but I just realized that TCE Bladesinger 6 could be better, due to how their Extra Attack feature is written, especially with Artillerist: I could attack once per turn with the rapier, then substitute one attack with a cantrip and then use my bonus action to use Eldritch Cannon.

Since a rod/staff/wand is not an actual weapon, (IIRC) I could benefit from both Bladesong (wielding Rapier in one hand) and Arcane Firearm (a rod or wand) or Eldritch Cannon in the other.
Gotta disagree. If it isn't a firearm, why call it that? If it just makes a wand/staff/rod into a spell focus (which is weak for a 5th level feature), why not just say so?

I can find no reference one way or the other.