The Stinger is pretty much the only anti-aircraft weapon I use.
On a different note, after playing Carnival a few times I've noticed really the only way for me to be successful is to creep around and basically camp out different places. Maybe its different in gametypes other than Team Deathmatch. What I don't like about Hardcore modes is that a lot of them turn out to be campfests since there is no killcam and you can hide in the corner and wait for someone to come by and they have no idea where they got shot from.
On a different note, after playing Carnival a few times I've noticed really the only way for me to be successful is to creep around and basically camp out different places. Maybe its different in gametypes other than Team Deathmatch. What I don't like about Hardcore modes is that a lot of them turn out to be campfests since there is no killcam and you can hide in the corner and wait for someone to come by and they have no idea where they got shot from.