Is there any official (manuals not ua) class related to firearms in 5e?

[Myth27]

My dm only allows manuals and there are firearms in this world, is there a way to make good use of them?

[Kane0]

DMG page 268, they're just ranged weapons so anything that works with that will work with guns. Crossbow Expert for example.

[JackPhoenix]

Depending on how your GM deals with reloading, most standard ranged builds could work. There's no class that does anything special with firearms.

Considering we don't know *how* your GM represents firearms mechanically, that's the best advice you'll get.

[Chronos]

There is no class based on the use of any specific weapon.

[Sigreid]

There's a firearm with some basic rules in Curse of Strahd, but it's really not worth using as written.

[ProsecutorGodot]

Technically, spells like Swift Quiver work with firearm ammunition. In the case of Swift Quiver, all it requires is the Quiver holding the ammo which means you'd have to keep your pellets (or whatever ammunition type your firearm uses) inside that quiver. It's weird, but it checks out.

Conjure Barrage/Volley works, Lightning Arrow works. It's pretty limited though

Ranger and Bard would be the best options I think. None of the subclasses really lend themselves well to using firearms though.