Provided is a device for the dispensing of powders of the type in which a generated gas flow entrains the powder to be dispensed and carries the powder from the device via a barrel. The barrel has a bore including a main portion with a continuous internal surface, and is characterized in that the length of the main portion is at least fifteen times its maximum internal diameter; and/or the internal bore of the main portion is tapered; and/or the barrel has an outwardly flared outlet portion.