Source: Tasha's Cauldron of Everything
You have a quick hand and keen eye when employing firearms, granting you the following benefits:
- Increase your Dexterity score by 1, to a maximum of 20.
- You gain proficiency with firearms (see “Firearms” in the Dungeon Master’s Guide).
- You ignore the loading property of firearms.
- Being within 5 feet of a hostile creature doesn’t impose disadvantage on your ranged attack rolls.