I've played the new Syndicate demo for a few sessions and upgraded my TAR-39 assault rifle to include a grenade launcher attachment.
I use it occasionally, as well as the regular (hand) grenades, but can't really tell when I'm replenishing either of those. They don't seem to fill when using the generic ammo boxes available at checkpoints, but their ammo does replenish, I just cant tell when.
I assume hand grenades can be replenished by picking up enemy hand grenades hacked in mid-air, but that's only my guess. Has anyone figured up what exactly replenishes this type of ammo?