A suppressor for a firearm includes a baffle stack having an outer surface, the baffle stack comprising a plurality of baffles that define an inner chamber coaxially aligned with a central axis of the baffle stack and a projectile pathway through the baffle stack along the central axis. An outer housing is around the baffle stack and has an inner surface separated from and confronting the outer surface of the baffle stack. An outer chamber is defined between the inner surface of the outer housing and the outer surface of the baffle stack. Flow-directing structures are in the outer chamber. An end cap is connected to a distal end of the outer housing and defines a central opening aligned with the central axis.