[RPG] Can you cast spells with a Somatic component if you’re holding a two-handed weapon


I have a halfling cleric of Bahamut who wears his holy symbol as an amulet around his neck as a spellcasting focus (so material components are not an issue).
However, as per this question, this does not cover the Somatic component of any spells he casts.

He also wields a light crossbow as his only weapon, which has the two-handed weapon property.
How does RAW handle Somatic casting when you're holding a two-handed weapon? Can I simply take a hand off my weapon, cast the spell, and re-grip all in the same action?
If not, has anyone run into this problem at their table before and how did you handle it?

Best Answer

Taking your hand off the weapon should not require any action expenditure - you are just letting go of it, same as if you dropped it.

You can then use your free object interaction to restore your grip after casting.

The PHB Errata says:

Two-Handed (p. 147). This property is relevant only when you attack with the weapon, not when you simply hold it.

So you can hold it with one hand while you are not attacking with it.